Articles de revues : « Heterostructures - Metal Nanoparticles »

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Chopra, Nitin, Junchi Wu et Paaras Agrawal. « Synthesis of Nanoscale Heterostructures Comprised of Metal Nanowires, Carbon Nanotubes, and Metal Nanoparticles : Investigation of Their Structure and Electrochemical Properties ». Journal of Nanomaterials 2015 (2015) : 1–13. http://dx.doi.org/10.1155/2015/125970.

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One-dimensional nanoscale heterostructures comprised of multisegment gold-nickel nanowires, carbon nanotube, and nickel nanoparticles were fabricated in a unique approach combining top-down and bottom-up assembly methods. Porous alumina template was utilized for sequential electrodeposition of gold and nickel nanowire segments. This was followed by chemical vapor deposition growth of carbon nanotubes on multisegment gold-nickel nanowires, where nickel segment also acted as a carbon nanotube growth catalyst. The aligned arrays of these gold-nickel-carbon nanotube heterostructures were released from porous alumina template and then subjected to wet-chemical process to be decorated with nickel/nickel oxide core/shell nanoparticles. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy were utilized for morphology, interface, defect, and structure characterization. The electrochemical performance of these heterostructures was studied using cyclic voltammetry method and the specific capacitance of various heterostructures was estimated and compared.

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Dorovskikh, Svetlana I., Evgeniia S. Vikulova, David S. Sergeevichev, Tatiana Ya Guselnikova, Ilya V. Korolkov, Anastasiya D. Fedorenko, Dmitriy A. Nasimov et al. « Heterostructures Based on Noble Metal Films with Ag and Au Nanoparticles : Fabrication, Study of In Vivo Biocompatibility and Antibacterial Activity ». Coatings 13, n^o 7 (19 juillet 2023) : 1269. http://dx.doi.org/10.3390/coatings13071269.

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In this work, approaches to the formation of multifunctional film heterostructures based on noble metals for the modification of the surface of implant materials (titanium alloy TiAl6V4 and carbon-fiber-reinforced polyetheretherketone CFR-PEEK) are developed. Such heterostructures consist of continuous layers of platinum (Pt) or iridium (Ir) and antibacterial components on their surface, namely silver (nanoparticles or discontinuous films) and gold (nanoparticles). Chemical or physical gas-phase deposition methods were used for their preparation. The influence of the concentration and form of the antibacterial component on the antibacterial activity and in vivo biocompatibility of the film structures was evaluated for the first time. Differences in the dynamics of silver dissolution depending on Ag concentration in the sample and the type of bottom surface (the noble metal layer = Ir, Pt or TiAl6V4) surfaces allowed us to better understand the nature of the antibacterial action against Staphylococcus aureus and Pseudomonas aeruginosa (S. aureus and P. aeruginosa) of Ag/M heterostructures. From in vivo histological studies using rats, the best biocompatibility was shown by the Ag/M heterostructure with a prolonged release of the low fraction of antibacterial component (Ag).

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Sun, Ying-Hui, Cong-Yan Mu, Wen-Gui Jiang, Liang Zhou et Rong-Ming Wang. « Interface modulation and physical properties of heterostructure of metal nanoparticles and two-dimensional materials ». Acta Physica Sinica 71, n^o 6 (2022) : 066801. http://dx.doi.org/10.7498/aps.71.20211902.

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<sec>Two-dimensional (2D) material has atomic smooth surface, nano-scale thickness and ultra-high specific surface area, which is an important platform for studying the interface interaction between metal nanoparticles (NPs) and 2D materials, and also for observing the surface atomic migration, structural evolution and aggregation of metal NPs in real time and <i>in situ</i>. By rationally designing and constructing the interfaces of metal NPs and 2D materials, the characterization of the interface structure on an atomic scale is very important in revealing the structure-property relationship. It is expected that the investigation is helpful in understanding the mechanism of interaction between metal and 2D materials and optimizing the performance of the devices based on metal-2D material heterojunctions.</sec><sec>In this review, the recent progress of interface modulation and physical properties of the heterostructure of metal NPs and 2D materials are summarized. The nucleation, growth, structural evolution and characterization of metal NPs on the surface of 2D materials are reviewed. The effects of metal NPs on the crystal structure, electronic state and energy band of 2D materials are analyzed. The possible interfacial strain and interfacial reaction are also included. Because of the modulation of electrical and optical properties of 2D materials, the performance of metal NPs-2D material based field effect transistor devices and optoelectronic devices are improved. This review is helpful in clarifying the physical mechanism of microstructure affecting the properties of metal NPs-2D material heterostructures on an atomic scale, and also in developing the metal-2D material heterostructures and their applications in the fields of electronic devices, photoelectric devices, energy devices, etc.</sec>

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Drozdov, AD, et J. deClaville Christiansen. « Modeling dielectric permittivity of polymer composites filled with transition metal dichalcogenide nanoparticles ». Journal of Composite Materials 54, n^o 25 (1 mai 2020) : 3841–55. http://dx.doi.org/10.1177/0021998320922601.

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A model is developed for the dielectric permittivity of polymer nanocomposites reinforced with transition metal dichalcogenide fillers at microwave frequencies. The model takes into account aggregation of nanoparticles into clusters (that involve both filler and matrix components) and the aspect ratio of aggregates. The governing equations involve four material parameters that are found by matching observations on the real and imaginary parts of the dielectric permittivity of polymers reinforced with MoS2 and WS2 micro- and nanospheres, MoS2 nanosheets and nanoflowers, and composite heterostructures formed by MoS2 and MoS2-CoS2 nanoparticles with graphene and reduced graphene oxide. Good agreement is demonstrated between results of simulation and the experimental data at frequencies in the S, X, and Ku bands of the electromagnetic spectrum. It is shown that composite heterostructures have superior dielectric properties compared with those of neat transition metal dichalcogenide nanoparticles.

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Ignat, Eugenia Corina, Doina Lutic, Gabriel Ababei et Gabriela Carja. « Novel Heterostructures of Noble Plasmonic Metals/Ga-Substituted Hydrotalcite for Solar Light Driven Photocatalysis toward Water Purification ». Catalysts 12, n^o 11 (2 novembre 2022) : 1351. http://dx.doi.org/10.3390/catal12111351.

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Heterostructures formed by close conjunctions of plasmonic metal nanoparticles and non-plasmonic (2D) lamellar nanostructures are receiving extensive interest as solar-light-driven photocatalysts for environmental pollutant remediation. Herein, the conjunction of plasmonic Au or Ag and Ga-substituted hydrotalcite are obtained by exploiting the manifestation of the structural “memory effect” of Ga-substituted hydrotalcite in the aqueous solutions of Au(CH3COO)3 and Ag2SO4, respectively. The 2D layered matrix of MgGaAl plays a dual function; it is involved in the synthesis of the plasmonic metal nanoparticles, and further, is acting as a support. The compressive investigations using X-ray diffraction (XRD), UV-diffuse reflectance spectroscopy (UVDR), infrared spectroscopy (FT-IR), transmission electron microscopy (TEM/HRTEM), high-angle annular dark-field imaging/scanning transmittance electron microscopy (HAADF/STEM) and X-ray photoelectron spectroscopy (XPS) describe structural, composition and nano/micromorphology characteristics of the novel heterostructures, while UVDR analysis afforded to study the features of their plasmonic responses. Results reveal that the catalysts are formed by close conjunction of small nanoparticles of Au or Ag (with a mean size less than 20 nm) that are formed on the larger particles of MgGaAl and own plasmonic features within the visible range. The catalysts performances were tested towards photocatalytic degradation of p-dichlorobenzene and 4-nitrophenol under solar light irradiation. Results revealed that the degradation of the pollutants is entangled to the plasmonic response of the heterostructured catalysts that is the key functionality in promoting photocatalysis and degrading the pollutants, under solar light irradiation. MgGaAl showed a very low photocatalytic activity when irradiated by UV or solar light. Notably, the heterostructured catalysts proceeded in good to excellent yield to remove the tested pollutants, under solar light irradiation. The sustainability of the novel catalysts was assessed through the kinetic analysis of the degradation processes of the tested pollutants and their mixture.

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Qu, Siqi, Jing Guan, Dongqi Cai, Qianshuo Wang, Xiuyun Wang, Wei Song et Wei Ji. « An Electrochromic Ag-Decorated WO3−x Film with Adjustable Defect States for Electrochemical Surface-Enhanced Raman Spectroscopy ». Nanomaterials 12, n^o 10 (11 mai 2022) : 1637. http://dx.doi.org/10.3390/nano12101637.

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Electrochemical surface-enhanced Raman scattering (EC-SERS) spectroscopy is an ultrasensitive spectro-electrochemistry technique that provides mechanistic and dynamic information on electrochemical interfaces at the molecular level. However, the plasmon-mediated photocatalysis hinders the intrinsic electrochemical behavior of molecules at electrochemical interfaces. This work aimed to develop a facile method for constructing a reliable EC-SERS substrate that can be used to study the molecular dynamics at electrochemical interfaces. Herein, a novel Ag-WO3−x electrochromic heterostructure was synthesized for EC-SERS. Especially, the use of electrochromic WO3−x film suppresses the influence of hot-electrons-induced catalysis while offering a reliable SERS effect. Based on this finding, the real electrochemical behavior of p-aminothiophenol (PATP) on Ag nanoparticles (NPs) surface was revealed for the first time. We are confident that metal-semiconductor electrochromic heterostructures could be developed into reliable substrates for EC-SERS analysis. Furthermore, the results obtained in this work provide new insights not only into the chemical mechanism of SERS, but also into the hot-electron transfer mechanism in metal-semiconductor heterostructures.

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Gilea, Diana, Radu G. Ciocarlan, Elena M. Seftel, Pegie Cool et Gabriela Carja. « Engineering Heterostructures of Layered Double Hydroxides and Metal Nanoparticles for Plasmon-Enhanced Catalysis ». Catalysts 12, n^o 10 (11 octobre 2022) : 1210. http://dx.doi.org/10.3390/catal12101210.

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Artificially designed heterostructures formed by close conjunctions of plasmonic metal nanoparticles (PNPs) and non-plasmonic (2D) lamellar nanostructures are receiving extensive interest. The synergistic interactions of the nanounits induce the manifestation of localized surface plasmon resonance (LSPR) in plasmonic metals in the specific environment of the 2D-light absorbing matrix, impacting their potential in plasmon enhanced catalysis. Specifically, layered double hydroxides (LDH) with the advantages of their unique 2D-layered structure, tuned optical absorption, ease of preparation, composition diversity, and high surface area, have emerged as very promising candidates for obtaining versatile and robust catalysts. In this review, we cover the available PNPs/LDH heterostructures, from the most used noble-metals plasmonic of Au and Ag to the novel non-noble-metals plasmonic of Cu and Ni, mainly focusing on their synthesis strategies toward establishing a synergistic response in the coupled nanounits and relevant applications in plasmonic catalysis. First, the structure–properties relationship in LDH, establishing the desirable features of the 2D-layered matrix facilitating photocatalysis, is shortly described. Then, we address the recent research interests toward fabrication strategies for PNPs/support heterostructures as plasmonic catalysts. Next, we highlight the synthesis strategies for available PNPs/LDH heterostructures, how these are entangled with characteristics that enable the manifestation of the plasmon-induced charge separation effect (PICS), co-catalytic effect, or nanoantenna effect in plasmonic catalysis with applications in energy related and environmental photocatalysis. Finally, some perspectives on the challenges and future directions of PNPs/LDHs heterostructures to improve their performance as plasmonic catalysts are discussed.

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Rehman, Khalil ur, Shaista Airam, Xiangyun Lin, Jian Gao, Qiang Guo et Zhipan Zhang. « In Situ Formation of Surface-Induced Oxygen Vacancies in Co9S8/CoO/NC as a Bifunctional Electrocatalyst for Improved Oxygen and Hydrogen Evolution Reactions ». Nanomaterials 11, n^o 9 (30 août 2021) : 2237. http://dx.doi.org/10.3390/nano11092237.

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Creating oxygen vacancies and introducing heterostructures are two widely used strategies in Co-based oxides for their efficient electrocatalytic performance, yet both strategies have rarely been used together to design a bifunctional electrocatalyst for an efficient overall water splitting. Herein, we propose a facile strategy to synthesize oxygen-defect-rich Co9S8/CoO hetero-nanoparticles with a nitrogen-doped carbon shell (ODR-Co9S8/CoO/NC) through the in situ conversion of heterojunction along with surface-induced oxygen vacancies, simply via annealing the precursor Co3S4/Co(OH)2/ZIF-67. The as-prepared ODR-Co9S8/CoO/NC shows excellent bifunctional catalytic activities, featuring a low overpotential of 217 mV at 10 mA cm−2 in the oxygen evolution reaction (OER) and 160 mV at 10 mA cm−2 in the hydrogen evolution reaction (HER). This performance excellency is attributed to unique heterostructure and oxygen defects in Co9S8/CoO nanoparticles, the current work is expected to offer new insights to the design of cost-effective, noble-metal-free electrocatalysts.

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Lord, Robert W., Cameron F. Holder, Julie L. Fenton et Raymond E. Schaak. « Seeded Growth of Metal Nitrides on Noble-Metal Nanoparticles To Form Complex Nanoscale Heterostructures ». Chemistry of Materials 31, n^o 12 (22 mai 2019) : 4605–13. http://dx.doi.org/10.1021/acs.chemmater.9b01638.

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Sbeta, Mohamed, et Abdullah Yildiz. « Optical response enhancement of GZO/p-Si heterostructures via metal nanoparticles ». Materials Research Express 6, n^o 8 (8 mai 2019) : 085018. http://dx.doi.org/10.1088/2053-1591/ab1c82.

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Dorovskikh, Svetlana I., Evgeniia S. Vikulova, David S. Sergeevichev, Tatiana Ya Guselnikova, Alexander A. Zheravin, Dmitriy A. Nasimov, Maria B. Vasilieva et al. « Biological Studies of New Implant Materials Based on Carbon and Polymer Carriers with Film Heterostructures Containing Noble Metals ». Biomedicines 10, n^o 9 (8 septembre 2022) : 2230. http://dx.doi.org/10.3390/biomedicines10092230.

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This paper presents pioneering results on the evaluation of noble metal film hetero-structures to improve some functional characteristics of carbon-based implant materials: carbon-composite material (CCM) and carbon-fiber-reinforced polyetheretherketone (CFR-PEEK). Metal-organic chemical vapor deposition (MOCVD) was successfully applied to the deposition of Ir, Pt, and PtIr films on these carriers. A noble metal layer as thin as 1 µm provided clear X-ray imaging of 1–2.5 mm thick CFR-PEEK samples. The coated and pristine CCM and CFR-PEEK samples were further surface-modified with Au and Ag nanoparticles (NPs) through MOCVD and physical vapor deposition (PVD) processes, respectively. The composition and microstructural features, the NPs sizes, and surface concentrations were determined. In vitro biological studies included tests for cytotoxicity and antibacterial properties. A series of samples were selected for subcutaneous implantation in rats (up to 3 months) and histological studies. The bimetallic PtIr-based heterostructures showed no cytotoxicity in vitro, but were less biocompatible due to a dense two-layered fibrous capsule. AuNP heterostructures on CFR-PEEK promoted cell proliferation in vitro and exhibited a strong inhibition of bacterial growth (p < 0.05) and high in vitro biocompatibility, especially Au/Ir structures. AgNP heterostructures showed a more pronounced antibacterial effect, while their in vivo biocompatibility was better than that of the pristine CFR-PEEK, but worse than that of AuNP heterostructures.

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Samoilova, Nadezhda A., Maria A. Krayukhina, Alexander A. Korlyukov, Zinaida S. Klemenkova, Alexander V. Naumkin et Yaroslav O. Mezhuev. « One-Pot Synthesis of Colloidal Hybrid Au (Ag)/ZnO Nanostructures with the Participation of Maleic Acid Copolymers ». Polymers 15, n^o 7 (27 mars 2023) : 1670. http://dx.doi.org/10.3390/polym15071670.

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One-pot synthesis of colloidal Au/ZnO and Ag/ZnO nanohybrid structures was carried out. The copolymers of maleic acid—poly(N-vinyl-2-pyrrolidone-alt-maleic acid), poly(ethylene-alt-maleic acid), or poly(styrene-alt-maleic acid) were used as templates for the sorption of cations of metals-precursors and stabilization of the resulting nanoheterostructures. Simultaneous production of two types of nanoparticles has been implemented under mild conditions in an aqueous alkaline medium and without additional reagents. Equimolar ratios of the metal cations and appropriate load on all copolymers were used: molar ratio of maleic acid monomeric units of copolymer/gold (silver)cations/zinc cations was 1/0.15/0.23 (1/0.3/0.15). The process of obtaining the heterostructures was studied using UV-Vis spectroscopy. The kinetics of the formation of heterostructures was influenced by the nature of the maleic acid copolymer and noble metal cations used. A high reaction rate was observed in the case of using zinc and gold cations-precursors and a copolymer of maleic acid with N-vinylpyrrolidone as a stabilizer of nanoparticles. The structure of the synthesized polymer-stabilized heterostructures was studied using instrumental methods of analysis—XPS, FTIR, PXRD, and TEM. Under the conditions used, stable colloidal solutions of heterodimers were obtained, and such structure can be converted to a solid state and back without loss of properties.

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Zheng, Guangchao, Zhuwen Chen, Kadir Sentosun, Ignacio Pérez-Juste, Sara Bals, Luis M. Liz-Marzán, Isabel Pastoriza-Santos, Jorge Pérez-Juste et Mei Hong. « Shape control in ZIF-8 nanocrystals and metal nanoparticles@ZIF-8 heterostructures ». Nanoscale 9, n^o 43 (2017) : 16645–51. http://dx.doi.org/10.1039/c7nr03739b.

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Mu, Congyan, Hao Li, Liang Zhou, Huanyu Ye, Rongming Wang et Yinghui Sun. « Construction of the Heterostructure of NiPt Truncated Octahedral Nanoparticle/MoS2 and Its Interfacial Structure Evolution ». Nanomaterials 13, n^o 11 (31 mai 2023) : 1777. http://dx.doi.org/10.3390/nano13111777.

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Interfacial atomic configuration plays a vital role in the structural stability and functionality of nanocomposites composed of metal nanoparticles (NPs) and two−dimensional semiconductors. In situ transmission electron microscope (TEM) provides a real−time technique to observe the interface structure at atomic resolution. Herein, we loaded bimetallic NiPt truncated octahedral NPs (TONPs) on MoS2 nanosheets and constructed a NiPt TONPs/MoS2 heterostructure. The interfacial structure evolution of NiPt TONPs on MoS2 was in situ investigated using aberration−corrected TEM. It was observed that some NiPt TONPs exhibited lattice matching with MoS2 and displayed remarkable stability under electron beam irradiation. Intriguingly, the rotation of an individual NiPt TONP can be triggered by the electron beam to match the MoS2 lattice underneath. Furthermore, the coalescence kinetics of NiPt TONPs can be quantitatively described by the relationship between neck radius (r) and time (t), expressed as rn = Kt. Our work offers a detailed analysis of the lattice alignment relationship of NiPt TONPs on MoS2, which may enlighten the design and preparation of stable bimetallic metal NPs/MoS2 heterostructures.

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Liu, Qing, Bo Wu, Mengyuan Li, Yuanyu Huang et Lele Li. « Heterostructures Made of Upconversion Nanoparticles and Metal–Organic Frameworks for Biomedical Applications ». Advanced Science 9, n^o 3 (17 novembre 2021) : 2103911. http://dx.doi.org/10.1002/advs.202103911.

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Li, Xiaolin, Yujie Ma, Zhi Yang, Shusheng Xu, Liangming Wei, Da Huang, Tao Wang, Nantao Hu et Yafei Zhang. « Hierarchical heterostructures based on prickly Ni nanowires/Cu2O nanoparticles with enhanced photocatalytic activity ». Dalton Transactions 45, n^o 17 (2016) : 7258–66. http://dx.doi.org/10.1039/c5dt04484g.

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Wang, Jianmin, Zhen Zhao, Chen Shen, Haopeng Liu, Xueyong Pang, Meiqi Gao, Juan Mu, Feng Cao et Guoqing Li. « Ni/NiO heterostructures encapsulated in oxygen-doped graphene as multifunctional electrocatalysts for the HER, UOR and HMF oxidation reaction ». Catalysis Science & ; Technology 11, n^o 7 (2021) : 2480–90. http://dx.doi.org/10.1039/d0cy02333g.

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A controlled scalable arc-discharge method was developed to produce metal/metal oxide nanoparticles encapsulated in graphene as excellent catalysts for multiple reactions, including HER, UOR, and the HMF oxidation reaction.

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Manoharan, Gririraj, Petra Bösel, Jannis Thien, Michael Holtmannspötter, Laura Meingast, Mercedes Schmidt, Henning Eickmeier et al. « Click-Functionalization of Silanized Carbon Nanotubes : From Inorganic Heterostructures to Biosensing Nanohybrids ». Molecules 28, n^o 5 (25 février 2023) : 2161. http://dx.doi.org/10.3390/molecules28052161.

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Here we present an approach to functionalize silanized single-walled carbon nanotubes (SWNTs) through copper-free click chemistry for the assembly of inorganic and biological nanohybrids. The nanotube functionalization route involves silanization and strain-promoted azide–alkyne cycloaddition reactions (SPACC). This was characterized by X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and Fourier transform infra-red spectroscopy. Silane–azide-functionalized SWNTs were immobilized from solution onto patterned substrates through dielectrophoresis (DEP). We demonstrate the general applicability of our strategy for the functionalization of SWNTs with metal nanoparticles (gold nanoparticles), fluorescent dyes (Alexa Fluor 647) and biomolecules (aptamers). In this regard, dopamine-binding aptamers were conjugated to the functionalized SWNTs to perform real-time detection of dopamine at different concentrations. Additionally, the chemical route is shown to selectively functionalize individual nanotubes grown on the surface of silicon substrates, contributing towards future nano electronic device applications.

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Wang, Shuping, Wendi Zhang, Zhijie Yang, Huiying Wei, Yanzhao Yang et Jingjing Wei. « Hierarchical Sheet-on-Sphere Heterostructures as Supports for Metal Nanoparticles : A Robust Catalyst System ». Catalysis Letters 149, n^o 9 (10 juin 2019) : 2492–99. http://dx.doi.org/10.1007/s10562-019-02858-9.

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Kozenkova, Elena, Kateryna Levada, Maria V. Efremova, Alexander Omelyanchik, Yulia A. Nalench, Anastasiia S. Garanina, Stanislav Pshenichnikov et al. « Multifunctional Fe3O4-Au Nanoparticles for the MRI Diagnosis and Potential Treatment of Liver Cancer ». Nanomaterials 10, n^o 9 (21 août 2020) : 1646. http://dx.doi.org/10.3390/nano10091646.

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Heterodimeric nanoparticles comprising materials with different functionalities are of great interest for fundamental research and biomedical/industrial applications. In this work, Fe3O4-Au nano-heterostructures were synthesized by a one-step thermal decomposition method. The hybrid nanoparticles comprise a highly crystalline 12 nm magnetite octahedron decorated with a single noble metal sphere of 6 nm diameter. Detailed analysis of the nanoparticles was performed by UV-visible spectroscopy, magnetometry, calorimetry and relaxometry studies. The cytotoxic effect of the nanoparticles in the human hepatic cell line Huh7 and PLC/PRF/5-Alexander was also assessed. These Fe3O4-Au bifunctional nanoparticles showed no significant cytotoxicity in these two cell lines. The nanoparticles showed a good theranostic potential for liver cancer treatment, since the r2 relaxivity (166.5 mM−1·s−1 and 99.5 mM−1·s−1 in water and HepG2 cells, respectively) is higher than the corresponding values for commercial T2 contrast agents and the Specific Absorption Rate (SAR) value obtained (227 W/gFe) is enough to make them suitable as heat mediators for Magnetic Fluid Hyperthermia. The gold counterpart can further allow the conjugation with different biomolecules and the optical sensing.

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Lin, Ye-Zhan, Kai Wang, Yu Zhang, Yi-Chuan Dou, Yi-Jin Yang, Mei-Ling Xu, Yanju Wang, Fu-Tian Liu et Kui Li. « Metal–organic framework-derived CdS–NiO heterostructures with modulated morphology and enhanced photocatalytic hydrogen evolution activity in pure water ». Journal of Materials Chemistry C 8, n^o 29 (2020) : 10071–77. http://dx.doi.org/10.1039/c9tc07042g.

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This work reported the uniform distribution of CdS nanoparticles over the MOF-derived porous NiO skeleton. With the PVP surface modification and the residual carbon, the formation of CdS-porous NiO exhibited an excellent photocatalytic performance.

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Pavlov, V. V., L. V. Lutsev, P. A. Usachev, A. A. Astretsov, A. I. Stognij, N. N. Novitskii et R. V. Pisarev. « Magnetic-field-induced photocurrent in metal-dielectric-semiconductor heterostructures based on cobalt nanoparticles SiO2(Co)/GaAs ». Journal of Magnetism and Magnetic Materials 400 (février 2016) : 290–94. http://dx.doi.org/10.1016/j.jmmm.2015.07.063.

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Khanam, Shomaila, et Sanjeeb Kumar Rout. « A Photocatalytic Hydrolysis and Degradation of Toxic Dyes by Using Plasmonic Metal–Semiconductor Heterostructures : A Review ». Chemistry 4, n^o 2 (15 mai 2022) : 454–79. http://dx.doi.org/10.3390/chemistry4020034.

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Converting solar energy to chemical energy through a photocatalytic reaction is an efficient technique for obtaining a clean and affordable source of energy. The main problem with solar photocatalysts is the recombination of charge carriers and the large band gap of the photocatalysts. The plasmonic noble metal coupled with a semiconductor can give a unique synergetic effect and has emerged as the leading material for the photocatalytic reaction. The LSPR generation by these kinds of materials has proved to be very efficient in the photocatalytic hydrolysis of the hydrogen-rich compound, photocatalytic water splitting, and photocatalytic degradation of organic dyes. A noble metal coupled with a low bandgap semiconductor result in an ideal photocatalyst. Here, both the noble metal and semiconductor can absorb visible light. They tend to produce an electron–hole pair and prevent the recombination of the generated electron–hole pair, which ultimately reacts with the chemicals in the surrounding area, resulting in an enhanced photocatalytic reaction. The enhanced photocatalytic activity credit could be given to the shared effect of the strong SPR and the effective separation of photogenerated electrons and holes supported by noble metal particles. The study of plasmonic metal nanoparticles onto semiconductors has recently accelerated. It has emerged as a favourable technique to master the constraint of traditional photocatalysts and stimulate photocatalytic activity. This review work focuses on three main objectives: providing a brief explanation of plasmonic dynamics, understanding the synthesis procedure and examining the main features of the plasmonic metal nanostructure that dominate its photocatalytic activity, comparing the reported literature of some plasmonic photocatalysts on the hydrolysis of ammonia borane and dye water treatment, providing a detailed description of the four primary operations of the plasmonic energy transfer, and the study of prospects and future of plasmonic nanostructures.

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Kumar, Mukesh, Himani Chauhan, Biswarup Satpati et Sasanka Deka. « Yolk Type Asymmetric Ag–Cu2O Hybrid Nanoparticles on Graphene Substrate as Efficient Electrode Material for Hybrid Supercapacitors ». Zeitschrift für Physikalische Chemie 233, n^o 1 (19 décembre 2018) : 85–104. http://dx.doi.org/10.1515/zpch-2017-1067.

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Abstract Yolk type asymmetric Ag–Cu2O hybrid nanostructures are in situ synthesized on reduced graphene oxide (RGO) sheets for the first time under one pot hydrothermal mild reaction condition. The co-reduction method provides a facile and straight forward approach to metal/metal oxide hybrid NPs growth on graphene nanosheets and the nano heterostructures are found to be homogeneously distributed over graphene sheets with unique yolk type morphology forming Ag–Cu2O/RGO nanocomposite (NC). The supercapacitor performances of the NCs are evaluated in aqueous 6.0 M KOH by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge (GCD) in two electrode cell assembly using Ag-Cu2O/RGO as electrode material. The ternary NCs exhibit excellent hybrid capacitance behavior having ~812 Fg−1 specific capacitance value with high energy density 27.2 Wh kg−1 and power density 285 W kg−1, respectively, at current density of 0.5 Ag−1 that suits for potential applications in hybrid capacitor. The high capacitance property of ternary NCs without use of binder can be attributed to excellent electronic/ionic conductivity due to presence of highly conductive graphene sheets in addition of noble Ag metal and unique yolk type morphology which causes faster electronic conduction among different components of the electrode material.

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Kumar, Arun, Raimondo Cecchini, Claudia Wiemer, Valentina Mussi, Sara De Simone, Raffaella Calarco, Mario Scuderi, Giuseppe Nicotra et Massimo Longo. « Phase Change Ge-Rich Ge–Sb–Te/Sb2Te3 Core-Shell Nanowires by Metal Organic Chemical Vapor Deposition ». Nanomaterials 11, n^o 12 (10 décembre 2021) : 3358. http://dx.doi.org/10.3390/nano11123358.

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Ge-rich Ge–Sb–Te compounds are attractive materials for future phase change memories due to their greater crystallization temperature as it provides a wide range of applications. Herein, we report the self-assembled Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires grown by metal-organic chemical vapor deposition. The core Ge-rich Ge–Sb–Te nanowires were self-assembled through the vapor–liquid–solid mechanism, catalyzed by Au nanoparticles on Si (100) and SiO2/Si substrates; conformal overgrowth of the Sb2Te3 shell was subsequently performed at room temperature to realize the core-shell heterostructures. Both Ge-rich Ge–Sb–Te core and Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires were extensively characterized by means of scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, Raman microspectroscopy, and electron energy loss spectroscopy to analyze the surface morphology, crystalline structure, vibrational properties, and elemental composition.

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Jang, Sanha, Kyeongmin Moon, Youchang Park, Sujung Park et Kang Hyun Park. « Recent Studies on Multifunctional Electrocatalysts for Fuel Cell by Various Nanomaterials ». Catalysts 10, n^o 6 (3 juin 2020) : 621. http://dx.doi.org/10.3390/catal10060621.

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Based on nanotechnology, nanocomposites are synthesized using nanoparticles (NP), which have some advantages in terms of multifunctional, economic, and environmental factors. In this review, we discuss the inorganic applications as well as catalytic applications of NPs. Recently, structural defects, heteroatomic doping, and heterostructures of such efficient ideal catalysts and their application as multifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting. It has been verified that the catalysts used in oxygen reduction reaction and OER can be used effectively in metal/air batteries. Moreover, it has been reported that high-efficiency catalysts are required to implement urea oxidation reaction (UOR), which involves a six-electron reaction, as an electrochemical reaction. We expect that this review can be applied to sustainable and diverse electrochemistry fields.

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Li, Yang, Xinxin Bi, Qingzhang You, Ze Li, Lisheng Zhang, Yan Fang et Peijie Wang. « Strong coupling with directional scattering features of metal nanoshells with monolayer WS₂ heterostructures ». Applied Physics Letters 121, n^o 2 (11 juillet 2022) : 021104. http://dx.doi.org/10.1063/5.0098064.

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Realizing and manipulating strong light–matter coupling in 2D monolayer semiconductors are of the utmost importance in the development of photonic devices. Hollow nanostructures of noble metals are particularly interesting because of their stronger local electromagnetic field compared with solid nanoparticles, which facilitate the strong coupling of single metal nanostructures. Here, the tunable single nanocavity plasmon–exciton coupling was demonstrated at room temperature in hybrid systems consisting of Ag@Au hollow nanocubes (HNCs) and monolayer WS2 underneath, where a large vacuum Rabi splitting of 131.3 meV was observed. Mode splitting can be clearly observed from the dark-field scattering spectrum of the single hybrid nanocavity, which is ascribed to the strong coupling between the nanocavity mode and the excitonic mode. Then, we used the finite difference time domain method to simulate these hybrid systems. By changing the thickness of the shell of the Ag@Au HNC, we can tune the surface plasmon resonance peak position of HNCs to match the exciton energy of the monolayer WS2. The strong couplings were realized via the calculated scattering spectra. The calculated results were consistent with the experimental results. Furthermore, the mode volume of different nanostructures was discussed, and the mode volume of HNCs is smaller than other solid ones at the same plasmonic resonance wavelength, which also indicates that its ability to restrict an electromagnetic field is stronger. This study provides an ideal platform for the strong coupling of a single nanocavity at room temperature and has broad application prospects in the field of single-photon devices.

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Lian, Tianquan. « (Invited) Efficient Hot Electron Transfer By Plasmon Induced Interfacial Charge Transfer Transitio ». ECS Meeting Abstracts MA2018-01, n^o 31 (13 avril 2018) : 1867. http://dx.doi.org/10.1149/ma2018-01/31/1867.

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Surface plasmon resonance in metal nanostructures has been widely used to enhance the efficiency of semiconductors and/or molecular chromophore based solar energy conversion devices by increasing absorption or energy transfer rates through the enhanced local field strength. In more recent years, it has been shown that excitation of plasmons in metal nanostructures can also lead to the injection of hot electrons into semiconductors and enhanced photochemistry. This novel mechanism suggests that plasmonic nanostructures can potentially function as a new class of widely tunable and robust light harvesting materials for solar energy conversion. More importantly, it provide a novel approach to access highly energetic and reactive states of metals that is difficult to utilize with thermal chemistry. However, plasmon-induced hot electron injections from metal to semiconductor or molecules are still inefficient because of the competing ultrafast hot electron relaxation processes within the metallic domain. In this talk, I will discuss a recent study on the key factors that limit the efficiency of plasmon induced hot electron transfer in colloidal quantum-confined semiconductor-gold nanorod heterostructures. These heterostructures provide a well-defined and systematically tunable model system for studying the mechanism of hot electron transfer. In CdSe NRs with Au tips, the distinct plasmon band of the Au nanoparticles was completely damped due to strong interaction with the CdSe domain. Using transient absorption spectroscopy, we show that optical excitation of plasmons in the Au tip leads to efficient hot electron injection into the semiconductor nanorod. In the presence of sacrificial electron donors, this plasmon induced hot electron transfer process can be utilized to drive photoreduction reactions under continuous illumination. We propose that the strong metal/semiconductor coupling in CdSe/Au hetersostructures leads to a new pathway for this surprising efficient hot electron transfer. In this plasmon induced interfacial charge transfer transition (PICTT) the a plasmon decay by direct excitation of an electron from the metal to semiconductor, bypassing the competition with hot electron transfer in metal. Ongoing studies are examining the generality of this mechanism and exploring possible approaches for improving its efficiency through controlling the size and shape of the plasmonic and excitonic domains. Reference [1]. Kaifeng Wu, Jinquan Chen, James R. McBride, Tianquan Lian, “Efficient hot-electron transfer by a plasmon-induced interfacial charge-transfer transition”, Science (2015), 349 (6248): 632. DOI: 10.1126/science.aac5443 [2]. Kaifeng Wu, William E. Rodríguez-Córdoba, Ye Yang, and Tianquan Lian, “Plasmon-Induced Hot Electron Transfer from the Au Tip to CdS Rod in CdS-Au Nanoheterostructures”, Nano Lett. (2013), 13(11), 5255-5263. DOI: 10.1021/nl402730m

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Shtansky, Dmitry V., Andrei T. Matveev, Elizaveta S. Permyakova, Denis V. Leybo, Anton S. Konopatsky et Pavel B. Sorokin. « Recent Progress in Fabrication and Application of BN Nanostructures and BN-Based Nanohybrids ». Nanomaterials 12, n^o 16 (16 août 2022) : 2810. http://dx.doi.org/10.3390/nano12162810.

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Due to its unique physical, chemical, and mechanical properties, such as a low specific density, large specific surface area, excellent thermal stability, oxidation resistance, low friction, good dispersion stability, enhanced adsorbing capacity, large interlayer shear force, and wide bandgap, hexagonal boron nitride (h-BN) nanostructures are of great interest in many fields. These include, but are not limited to, (i) heterogeneous catalysts, (ii) promising nanocarriers for targeted drug delivery to tumor cells and nanoparticles containing therapeutic agents to fight bacterial and fungal infections, (iii) reinforcing phases in metal, ceramics, and polymer matrix composites, (iv) additives to liquid lubricants, (v) substrates for surface enhanced Raman spectroscopy, (vi) agents for boron neutron capture therapy, (vii) water purifiers, (viii) gas and biological sensors, and (ix) quantum dots, single photon emitters, and heterostructures for electronic, plasmonic, optical, optoelectronic, semiconductor, and magnetic devices. All of these areas are developing rapidly. Thus, the goal of this review is to analyze the critical mass of knowledge and the current state-of-the-art in the field of BN-based nanomaterial fabrication and application based on their amazing properties.

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Zhang, Guangqiang, Hong Su et Yan Zhang. « Construction of Glutinous Rice Potpourri-like MOTT−Schottky Ni/CeO2 Heterojunction Nanosheets for Robust Electrochemical Water Reduction ». Energies 15, n^o 24 (13 décembre 2022) : 9443. http://dx.doi.org/10.3390/en15249443.

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The development of efficient non-precious metal electrocatalysts through more economical and safe methods is consistent with the goals of sustainable development and accelerating the achievement of “carbon neutrality” in the 21st century but remains potentially challenging. Mott–Schottky heterojunction interfaces generated from metal/semiconductor have been a hot topic of recent research because of the unique built-in electric field effect which allows the preparation of more superior catalysts for water electrolysis. Herein, a glutinous rice potpourri-like Mott–Schottky two-dimensional (2D) nanosheet (abbreviated as Ni/CeO2 HJ-NSs) electrocatalyst composed of metal nickel (Ni) and cerium oxide (CeO2) hetero-nanoparticles was synthesized by a simple and scalable self-assembly and thermal reduction strategy. The experimental results and mechanistic analysis show that the Mott–Schottky heterojunction interface composed of metallic Ni and n-type semiconductor CeO2 with built-in electric field induces the electron redistribution at the interface to accelerate the dissociation of water and the binding of reaction intermediates, thus achieving lower water dissociation energy and more thermoneutral ΔGH* value to expedite the kinetics of the hydrogen evolution reaction (HER). Thus, the prepared Ni/CeO2 HJ-NSs exhibit excellent HER catalytic performance in 1 M KOH electrolyte with an overpotential of only 72 mV at 10 mA cm−2, as well as a moderate Tafel slope of 65 mV dec−1 and an extraordinary long-term stability over 50 h, laying a solid foundation for further in-depth investigation. The synthesis of splendid electrocatalysts by exploiting the metal/semiconductor interface effect provides an innovative way for the future generation of Mott–Schottky-based heterostructures with three or more heterocompositions with two or more heterojunction interfaces.

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Li, Xinyu, Xinfeng Zhu, Junfeng Wu, Hongbin Gao, Weichun Yang et Xiaoxian Hu. « Enhanced Heterogeneous Peroxymonosulfate Activation by MOF-Derived Magnetic Carbonaceous Nanocomposite for Phenol Degradation ». Materials 16, n^o 9 (24 avril 2023) : 3325. http://dx.doi.org/10.3390/ma16093325.

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Degradation efficiency and catalyst stability are crucial issues in the control of organic compounds in wastewater by advanced oxidation processes (AOPs). However, it is difficult for catalysts used in AOPs to have both high catalytic activity and high stability. Combined with the excellent activity of cobalt/copper oxides and the good stability of carbon, highly dispersed cobalt-oxide and copper-oxide nanoparticles embedded in carbon-matrix composites (Co-Cu@C) were prepared for the catalytic activation of peroxymonosulfate (PMS). The catalysts exhibited a stable structure and excellent performance for complete phenol degradation (20 mg L−1) within 5 min in the Cu-Co@C-5/PMS system, as well as low metal-ion-leaching rates and great reusability. Moreover, a quenching test and an EPR analysis revealed that ·OH, O2·−, and 1O2 were generated in the Co-Cu@C/PMS system for phenol degradation. The possible mechanism for the radical and non-radical pathways in the activation of the PMS by the Co-Cu@C was proposed. The present study provides a new strategy with which to construct heterostructures for environmentally friendly and efficient PMS-activation catalysts.

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Ling, Min, et Christopher S. Blackman. « Gas-phase synthesis of hybrid nanostructured materials ». Nanoscale 10, n^o 48 (2018) : 22981–89. http://dx.doi.org/10.1039/c8nr06257a.

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A chemical vapour deposition route is introduced to construct nano-heterostructured thin film of noble metal or their oxide nanoparticles decorating on 1D WO₃ nanorods. The size of nanoparticle is able to be easily tuned by controlling the deposition time showing enhanced photocatalytic property.

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Taffelli, Alberto, Sandra Dirè, Alberto Quaranta et Lucio Pancheri. « MoS2 Based Photodetectors : A Review ». Sensors 21, n^o 8 (14 avril 2021) : 2758. http://dx.doi.org/10.3390/s21082758.

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Photodetectors based on transition metal dichalcogenides (TMDs) have been widely reported in the literature and molybdenum disulfide (MoS2) has been the most extensively explored for photodetection applications. The properties of MoS2, such as direct band gap transition in low dimensional structures, strong light–matter interaction and good carrier mobility, combined with the possibility of fabricating thin MoS2 films, have attracted interest for this material in the field of optoelectronics. In this work, MoS2-based photodetectors are reviewed in terms of their main performance metrics, namely responsivity, detectivity, response time and dark current. Although neat MoS2-based detectors already show remarkable characteristics in the visible spectral range, MoS2 can be advantageously coupled with other materials to further improve the detector performance Nanoparticles (NPs) and quantum dots (QDs) have been exploited in combination with MoS2 to boost the response of the devices in the near ultraviolet (NUV) and infrared (IR) spectral range. Moreover, heterostructures with different materials (e.g., other TMDs, Graphene) can speed up the response of the photodetectors through the creation of built-in electric fields and the faster transport of charge carriers. Finally, in order to enhance the stability of the devices, perovskites have been exploited both as passivation layers and as electron reservoirs.

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Yu, Paul K. L., Edward T. Yu et De Li Wang. « Advances in Semiconductor Nanostructures for Photonic Applications ». Advanced Materials Research 410 (novembre 2011) : 36. http://dx.doi.org/10.4028/www.scientific.net/amr.410.36.

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In this paper we present the concept and demonstration of novel photovoltaic and electro-optic devices, and photoelectrochemical cells based on various semiconductor nanostructures, specifically compound semiconductor quantum wells and nanowires, and the use of plasmonic and related scattering effects from metal or dielectric nanoparticles to increase efficiency of optical absorption. Quantum-well solar cells were fabricated with scattering from metallic or dielectric nanostructures incorporated to direct incident photons into lateral, optically confined paths with high electromagnetic field intensity within relatively thin multiple-quantum-well regions to maximize quantum efficiency of photon absorption. The internal structure of quantum wells in quantum-well solar cells was also analyzed and characterized; the incorporation of a suitable potential step within each quantum well was explored for improvement in power conversion efficiency. Vertical nanowire arrays were engineered to optimize optical confinement within the nanowires, and core-shell heterostructures were employed to achieve broad-spectrum absorption while maintaining high open-circuit voltages. Large linear electro-optic effect is observed in the nanowire arrays. Branched nanowire photoelectrochemical cells were also made and characterized for their spectral incident photon-to-current conversion efficiency. These works have been sponsored by U.S. Department of Energy and National Science Foundation.

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Qiu, Bo, Xin Xiao, Min Zhang, Yue Mao et Xiaoheng Liu. « Noble metal enhanced photocatalytic activity of heterostructured TiO2 spheres with tunable interiors and shells ». Functional Materials Letters 13, n^o 08 (novembre 2020) : 2050039. http://dx.doi.org/10.1142/s1793604720500393.

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Heterostructured TiO2 spheres with tunable interiors and shells were prepared by self-template technology. This structure is composed of a hollow shell and an inner core which can enhance light scattering in the hollow space and provide a large surface to generate sufficient active sites. Besides, the nanosheets grown on the shell layer not only increased their specific surface area, but also exposed more surface-active sites. The performance of photocatalysts was estimated by the RhB decolorization, and experimental results show that the photoactivity can be greatly improved by depositing noble metal nanoparticles. It improves the efficiency of charge utilization and enhances the overall catalytic performance from the three stages of charge carrier generation, separation and surface reaction. The strong metal–support interaction (SMSI) between the noble metal nanoparticles and the oxide support has been proven to inhibit the supported precious metal, one strategy for nanoparticle aggregation and growth. On the one hand, the nanoshells isolate the precious metal nanoparticles from each other, preventing the aggregation of metal nanoparticles.

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De Sanctis, Adolfo, Jake Mehew, Monica Craciun et Saverio Russo. « Graphene-Based Light Sensing : Fabrication, Characterisation, Physical Properties and Performance ». Materials 11, n^o 9 (18 septembre 2018) : 1762. http://dx.doi.org/10.3390/ma11091762.

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Graphene and graphene-based materials exhibit exceptional optical and electrical properties with great promise for novel applications in light detection. However, several challenges prevent the full exploitation of these properties in commercial devices. Such challenges include the limited linear dynamic range (LDR) of graphene-based photodetectors, the lack of efficient generation and extraction of photoexcited charges, the smearing of photoactive junctions due to hot-carriers effects, large-scale fabrication and ultimately the environmental stability of the constituent materials. In order to overcome the aforementioned limits, different approaches to tune the properties of graphene have been explored. A new class of graphene-based devices has emerged where chemical functionalisation, hybridisation with light-sensitising materials and the formation of heterostructures with other 2D materials have led to improved performance, stability or versatility. For example, intercalation of graphene with FeCl 3 is highly stable in ambient conditions and can be used to define photo-active junctions characterized by an unprecedented LDR while graphene oxide (GO) is a very scalable and versatile material which supports the photodetection from UV to THz frequencies. Nanoparticles and quantum dots have been used to enhance the absorption of pristine graphene and to enable high gain thanks to the photogating effect. In the same way, hybrid detectors made from stacked sequences of graphene and layered transition-metal dichalcogenides enabled a class of devices with high gain and responsivity. In this work, we will review the performance and advances in functionalised graphene and hybrid photodetectors, with particular focus on the physical mechanisms governing the photoresponse, the performance and possible future paths of investigation.

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Zhang, Lijia, Zhongbin Luo, Lingshan Su et Dianping Tang. « A surface plasmon resonance enhanced photoelectrochemical immunoassay based on perovskite metal oxide@gold nanoparticle heterostructures ». Analyst 144, n^o 19 (2019) : 5717–23. http://dx.doi.org/10.1039/c9an01395d.

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Lin, Shali, Xiaohu Mi, Lei Xi, Jinping Li, Lei Yan, Zhengkun Fu et Hairong Zheng. « Efficient Reduction Photocatalyst of 4-Nitrophenol Based on Ag-Nanoparticles-Doped Porous ZnO Heterostructure ». Nanomaterials 12, n^o 16 (19 août 2022) : 2863. http://dx.doi.org/10.3390/nano12162863.

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Oxide-supported Ag nanoparticles have been widely reported as a good approach to improve the stability and reduce the cost of photocatalysts. In this work, a Ag-nanoparticles-doped porous ZnO photocatalyst was prepared by using metal–organic frameworks as a sacrificial precursor and the catalytic activity over 4-nitrophenol was determined. The Ag-nanoparticles-doped porous ZnO heterostructure was evaluated by UV, XRD, and FETEM, and the catalytic rate constant was calculated by the change in absorbance value at 400 nm of 4-nitrophenol. The photocatalyst with a heterogeneous structure is visible, light-responsive, and beneficial to accelerating the catalytic rate. Under visible light irradiation, the heterostructure showed excellent catalytic activity over 4-nitrophenol due to the hot electrons induced by the localized surface plasmon resonance of Ag nanoparticles. Additionally, the catalytic rates of 4 nm/30 nm Ag nanoparticles and porous/nonporous ZnO were compared. We found that the as-prepared Ag-nanoparticles-doped porous ZnO heterostructure catalyst showed enhanced catalytic performance due to the synergetic effect of Ag nanoparticles and porous ZnO. This study provides a novel heterostructure photocatalyst with potential applications in solar energy and pollutant disposal.

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Steimle, Benjamin C., Julie L. Fenton et Raymond E. Schaak. « Rational construction of a scalable heterostructured nanorod megalibrary ». Science 367, n^o 6476 (23 janvier 2020) : 418–24. http://dx.doi.org/10.1126/science.aaz1172.

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Integrating multiple materials in arbitrary arrangements within nanoparticles is a prerequisite for advancing many applications. Strategies to synthesize heterostructured nanoparticles are emerging, but they are limited in complexity, scope, and scalability. We introduce two design guidelines, based on interfacial reactivity and crystal structure relations, that enable the rational synthesis of a heterostructured nanorod megalibrary. We define synthetically feasible pathways to 65,520 distinct multicomponent metal sulfide nanorods having as many as 6 materials, 8 segments, and 11 internal interfaces by applying up to seven sequential cation-exchange reactions to copper sulfide nanorod precursors. We experimentally observe 113 individual heterostructured nanorods and demonstrate the scalable production of three samples. Previously unimaginable complexity in heterostructured nanorods is now routinely achievable with simple benchtop chemistry and standard laboratory glassware.

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Tang, Tang, Wen-Jie Jiang, Shuai Niu, Lu-Pan Yuan, Jin-Song Hu et Li-Jun Wan. « Hetero-coupling of a carbonate hydroxide and sulfide for efficient and robust water oxidation ». Journal of Materials Chemistry A 7, n^o 38 (2019) : 21959–65. http://dx.doi.org/10.1039/c9ta07882g.

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A metal sulfide and metal carbonate hydroxide heterostructure featuring a unique “nanoparticle-in-nanosheet” structure with abundant accessible hetero-interfaces is developed for efficient and robust water oxidation.

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Hsiao, Shan-Yuan, En-Xuan Lin et Pei-Yuin Keng. « Facile Synthesis of Carbon- and Nitrogen-Doped Iron Borate as a Highly Efficient Single-Component Heterogeneous Photo-Fenton Catalyst under Simulated Solar Irradiation ». Nanomaterials 11, n^o 11 (26 octobre 2021) : 2853. http://dx.doi.org/10.3390/nano11112853.

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The development of a heterogeneous catalyst for use in environmental remediation remains a challenging and attractive research endeavor. Specifically, for Fenton reactions, most research approaches have focused on the preparation of iron-containing heterostructures as photo-Fenton catalysts that utilize visible light for enhancing the degradation efficiency. Herein, the synthesis and novel application of C,N-doped iron borates are demonstrated as single-component heterogeneous photo-Fenton catalysts with high Fenton activity under visible light. Under the optimal conditions, 10 mg of the catalyst is shown to achieve effective degradation of 10 ppm methylene blue (MB) dye, Rhodamine B (RhB) dye, and tetracycline (TC) under simulated solar irradiation with a first-order rate constant of k = 0.218 min−1, 0.177 min−1, and 0.116 min−1, respectively. Using MB as a model system, the C,N-doped iron borate exhibits 10- and 26-fold increases in catalytic activity relative to that of the 50 nm hematite nanoparticles and that of the non-doped iron borate, respectively, in the presence of H2O2 under the simulated solar irradiation. Furthermore, the optimum reaction conditions used only 320 equivalents of H2O2 with respect to the concentration of dye, rather than the several thousand equivalents of H2O2 used in conventional heterogeneous Fenton catalysts. In addition, the as-prepared C,N-doped iron borate achieves 75% MB degradation after 20 min in the dark, thus enabling the continuous degradation of pollutants at night and in areas with poor light exposure. The stability and recyclability of C,N-doped iron borate for the oxidation of MB was demonstrated over three cycles with insignificant loss in photo-Fenton activity. The high Fenton activity of the C,N-doped iron borate is considered to be due to the synergistic action between the negatively-charged borate ligands and the metal center in promoting the Fenton reaction. Moreover, carbon and nitrogen doping are shown to be critical in modifying the electronic structure and increasing the conductivity of the catalyst. In view of its synthetic simplicity, high efficiency, low cost of reagents, and minimal cost of operation (driven by natural sunlight), the as-prepared heterogeneous single-component metal borate catalyst has potential application in the industrial treatment of wastewater.

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CHAN, YIN THAI. « HETEROSTRUCTURED HYBRID COLLOIDAL SEMICONDUCTOR NANOCRYSTALS ». COSMOS 06, n^o 02 (décembre 2010) : 235–45. http://dx.doi.org/10.1142/s0219607710000589.

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Significant efforts in the field of colloidal semiconductor particles have been dedicated to the fabrication and study of hybrid metal–semiconductor nanoheterostructures, where the incorporation of the metal moiety may potentially enhance and/or expand existing applications of semiconductor nanoparticles. Many of these metal–semiconductor nanostructured constructs exhibit physical properties not found in either of their metal or semiconductor components, providing many opportunities for further investigation into interface and coupling effects between the two materials. We review some of the key research endeavors in this area, focusing mainly on the synthesis of the materials and the characterization of the various metal–semiconductor constructs, and highlighting some of the unique applications that have emerged from these efforts.

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Tang, Hong-Liang, Xiao-Jun Sun et Feng-Ming Zhang. « Development of MOF-based heterostructures for photocatalytic hydrogen evolution ». Dalton Transactions 49, n^o 35 (2020) : 12136–44. http://dx.doi.org/10.1039/d0dt02309d.

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The schematic shows the types of MOF based heterojunction materials for photocatalytic hydrogen evolution, including metal nanoparticle/MOF, inorganic semiconductor/MOF, MOF/g-C₃N₄ and MOF/COF heterostructures.

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Kai, Shuangshuang, Baojuan Xi, Xiaolei Liu, Lin Ju, Peng Wang, Zhenyu Feng, Xiaojian Ma et Shenglin Xiong. « An innovative Au-CdS/ZnS-RGO architecture for efficient photocatalytic hydrogen evolution ». Journal of Materials Chemistry A 6, n^o 7 (2018) : 2895–99. http://dx.doi.org/10.1039/c7ta10958j.

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An innovative CdS/ZnS-RGO hybrid is synthesizedviaan one-pot hydrothermal method. The further introduction of Au nanoparticles enables the composite with the merits of heterostructured semiconductor/semiconductor junction benefiting the hole transfer, as well as graphene and noble metal favorable for electron transportation.

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Kumar, Mohit, et Challapali Subrahmanyam. « (Digital Presentation) Plasmonic Enhanced CuBi₂O₄ Photocathode for Solar Driven Water Splitting ». ECS Meeting Abstracts MA2022-02, n^o 50 (9 octobre 2022) : 2459. http://dx.doi.org/10.1149/ma2022-02502459mtgabs.

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Hydrogen is a fuel for sustainable and renewable energy development that emits no carbon dioxide when compared to traditional fossil fuels. Photoelectrochemical (PEC) water splitting is a sustainable method of converting solar energy that falls on earth into useful chemical fuels. However, the sluggish surface reaction kinetics, high cost, and low natural abundance limit the use of photoelectrodes for practical application. It is critical to developing effective and resilient photoelectrodes that provide high efficiency with good stability. Copper based oxides like CuO, Cu2O, CuBi2O4, CuFeO2, and Cu3VO4 are some of the most well-known low-cost materials with apt band gap and band edges for proton reduction reaction. Among them, CuO is one of the most extensively researched photocathodic materials for PEC water splitting owing to its natural abundance and facile synthesis. However, the photocorrosion problem at CuO limits its use in practical application. The conduction band of CuO is contributed by Cu 3d bands which easily get reduced to Cu0 on photoexcited electron diffuse to conduction band. On the other hand, CuBi2O4 is ternary metal oxide which is more resistant and forbids photocorrosion owing to it conduction band contributed by Bi atom orbitals rather than Cu orbitals1. Metal sulfides like Sb2S3 is good photo-absorber material for solar cells consists of non-toxic and low-cost metal. It has favorable band gap and conduction band and valence band alignment for proton reduction reaction. The type II heterojunction between CuBi2O4 and Sb2S3 can present effective strategy of charge separation and enhanced photoconversion. The plasmon behavior of metal NPs is widely studied in PEC to further improve the photoelectrochemical performance of the photoelectrodes. Plasmonic metal nanoparticles (NPs) absorb light of a threshold wavelength and vibrate emitting out the hot electrons2. Adding Au plasmonic NPs to the photoelectrode might increase the charge carrier concentration, enhance the PEC efficiency, and boost hydrogen production. The objectives of this study are to investigate fabrication of CuBi2O4/Sb2S3 heterojunction and investigate the dual role of plasmonic Au NPs sandwiched between CuBi2O4/Sb2S3 heterojunction. This heterojunction is developed through three synthesis process: synthesis of CuBi2O4 microrods (MRs) through co-precipitation, Sb2S3 plates via a hybrid chemical bath deposition, and Au NPs via seed-assisted synthesis. XRD, SEM, TEM, and XPS are used to examine the CuBi2O4/Au/Sb2S3, CuBi2O4/Sb2S3, and CuBi2O4/Au heterostructures that were synthesized. At 0 VRHE, the photocurrent of CuBi2O4/Au/Sb2S3 (-3.12 mA.cm-2) was > 200 percent greater than that of pristine CuBi2O4 (-1.45 mA.cm-2), Sb2S3 (-1.02 mA.cm-2), and CuBi2O4/Sb2S3 (-2.15 mA.cm-2). Impedance spectroscopy revealed that CuBi2O4/Au/Sb2S3 has the lowest charge transfer resistance value when compared to the pristines. Stability tests revealed the superior stability of CuBi2O4/Au/Sb2S3 compared to their counterparts3. The increase in photoelectrode PEC activity can be attributed to: (i) effective heterojunction formation for facile charge transfer, (ii) increased light absorption, (iii) incorporation of plasmonic Au NPs increased charge carrier concentration, and (iv) Au NPs also served as a relay for charge transfer between CuBi2O4 and Sb2S3 due to their metallic properties, which increased photoelectrode conductivity. The synergistic effect of fabricated CuBi2O4/Sb2S3 heterojunction and dual role of Au NPs sandwiched resulted in improved PEC conversion and boosted hydrogen evolution. The findings of this study will pave the way for photoelectrodes to be sandwiched between plasmonic NPs through a heterojunction interface that boosts hydrogen production. References (1) Li, C.; He, J.; Xiao, Y.; Li, Y.; Delaunay, J. J. Earth-Abundant Cu-Based Metal Oxide Photocathodes for Photoelectrochemical Water Splitting. Energy Environ. Sci. 2020, 13 (10), 3269–3306. https://doi.org/10.1039/d0ee02397c. (2) Subramanyam, P.; Meena, B.; Biju, V.; Misawa, H.; Challapalli, S. Emerging Materials for Plasmon-Assisted Photoelectrochemical Water Splitting. J. Photochem. Photobiol. C Photochem. Rev. 2022, 51 (November 2021), 100472. https://doi.org/10.1016/j.jphotochemrev.2021.100472. (3) Kumar, M.; Ghosh, C. C.; Meena, B.; Ma, T.; Subrahmanyam, C. Plasmonic Au Nanoparticle Sandwiched CuBi2O4 /Sb2S3 Photocathode with Multi-Mediated Electron Transfer for Efficient Solar Water Splitting. Sustain. Energy Fuels 2022. https://doi.org/10.1039/D2SE00600F. Figure 1

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Deng, Jie, Wei Chu, Bo Wang, Wen Yang et X. S. Zhao. « Mesoporous Ni/Ce1−xNixO2−y heterostructure as an efficient catalyst for converting greenhouse gas to H2 and syngas ». Catalysis Science & ; Technology 6, n^o 3 (2016) : 851–62. http://dx.doi.org/10.1039/c5cy00893j.

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A heterostructure of highly dispersed Ni nanoparticles in pore channels of Ni–CeO₂ solid solution, having excellent thermo-stability, redox properties, and metal/support synergy, is identified as an efficient nanocatalyst for converting greenhouse gas into H₂ energy and syngas.

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Zhao, Gege, Nianqiao Qin, An Pan, Xiaoyan Wu, Chuanyi Peng, Fei Ke, Mudassar Iqbal, Karna Ramachandraiah et Jing Zhu. « Magnetic Nanoparticles@Metal-Organic Framework Composites as Sustainable Environment Adsorbents ». Journal of Nanomaterials 2019 (27 octobre 2019) : 1–11. http://dx.doi.org/10.1155/2019/1454358.

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Metal-organic frameworks (MOFs) are an intriguing class of porous inorganic-organic hybrid networks synthesized from metal ions with multidentate organic ligands. MOFs have uniform and tunable cavities and tailorable chemistry, making them promising materials for hazardous component removal from the environment. Controllable integration of magnetic nanoparticles (NPs) and MOFs is leading to the creation of many novel multifunctional MOF-based composites, which exhibit advanced performance that is superior to both of the individual units. This review summarizes the recent significant advances in the development of MOF-based magnetic heterostructure materials for the removal of hazardous contaminants from the environment. The successful methods reported till date for the magnetic MOF synthesis are also provided. In the final section, we provide our views on the future development of the magnetic MOF heterostructure materials for the pollution management.

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Jain, Noopur, Ahin Roy et Sreejith Nair. « Reduced SrTiO3-supported Pt–Cu alloy nanoparticles for preferential oxidation of CO in excess hydrogen ». Nanoscale 11, n^o 46 (2019) : 22423–31. http://dx.doi.org/10.1039/c9nr07664f.

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Wenelska, Karolina, Martyna Trukawka, Wojciech Kukulka, Xuecheng Chen et Ewa Mijowska. « Co-Existence of Iron Oxide Nanoparticles and Manganese Oxide Nanorods as Decoration of Hollow Carbon Spheres for Boosting Electrochemical Performance of Li-Ion Battery ». Materials 14, n^o 22 (15 novembre 2021) : 6902. http://dx.doi.org/10.3390/ma14226902.

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Here, we report that mesoporous hollow carbon spheres (HCS) can be simultaneously functionalized: (i) endohedrally by iron oxide nanoparticle and (ii) egzohedrally by manganese oxide nanorods (FexOy/MnO2/HCS). Detailed analysis reveals a high degree of graphitization of HCS structures. The mesoporous nature of carbon is further confirmed by N2 sorption/desorption and transmission electron microscopy (TEM) studies. The fabricated molecular heterostructure was tested as the anode material of a lithium-ion battery (LIB). For both metal oxides under study, their mixture stored in HCS yielded a significant increase in electrochemical performance. Its electrochemical response was compared to the HCS decorated with a single component of the respective metal oxide applied as a LIB electrode. The discharge capacity of FexOy/MnO2/HCS is 1091 mAhg−1 at 5 Ag–1, and the corresponding coulombic efficiency (CE) is as high as 98%. Therefore, the addition of MnO2 in the form of nanorods allows for boosting the nanocomposite electrochemical performance with respect to the spherical nanoparticles due to better reversible capacity and cycling performance. Thus, the structure has great potential application in the LIB field.

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Xu, Zhixiao, et Xiaolei Wang. « Nickel-Molybdenum Carbide/Nitrogen-Doped Carbon Mott-Schottky Nanoarray for Water Spitting ». ECS Meeting Abstracts MA2022-01, n^o 55 (7 juillet 2022) : 2307. http://dx.doi.org/10.1149/ma2022-01552307mtgabs.

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Electrochemical water splitting, composed of two half reactions: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is under intensive research to the development of H2 fuels to replace fossil fuels. Since both reactions are sluggish, catalysts are usually required to boost them. The state-of-the-art catalysts for both reactions are based on noble metals, such as Pt-based catalysts for HER and Ir or Ru-based catalysts for OER. Unfortunately, the high price and scarcity of these noble metals suppress the widespread application of water splitting. Hence, it is imperative to develop active, durable, low-cost and earth-abundant non-noble-metal electrocatalysts.[1] Among them, molybdenum carbide (Mo2C) has garnered tremendous attention as HER/OER catalysts owing to its Pt-like electronic structure and wide-pH-range catalytic performance. [2] Unfortunately, the catalytic activity of Mo2C towards HER or OER is still inferior to most advanced catalysts. One effective strategy to enhance electrocatalytic performance involves coupling and doping of Mo2C with late transition metals, e.g., Fe, Co, and Ni, which modifies electronic structure and adds active sites, metal-Mo2C interfaces. Unfortunately, similar to Mo2C, metal nanoparticles also tend to aggregate during preparation and operation. A semiconductive carbon catalyst support alleviating aggregation is usually the solution by not only conformally dispersing nanocatalysts but also providing heteroatom dopants and forming metal-semiconductor Mott-Schottky interface for further enhancing catalytic activity.[3] Besides the selection of catalysts with optimized structure and composition at the material level, the structure of electrodes derived from assembled catalysts at the device level also have a crucial influence on the water electrolyzer. Compared with powdery electrocatalysts with relatively large overpotential and easier peeling off from the electrode, self-supported hierarchical nanoarrayed electrodes are more promising for water electrolyzer because these electrodes facilitate transportation of charges and matter and thus reaction kinetics during HER/OER due to binder-free feature, catalysts-substrate seamless contact and highly exposed surface area.[4] We develop here the making of nickel-molybdenum carbide heterostructures embedded in large-area (100 cm2) hierarchically assembled nitrogen-enriched carbon, forming Mott-Schottky array on nickel foam (Ni-Mo2C/NC@NF).[5] The Ni-Mo2C/NC array is directly applied as the bifunctional catalyst with high activity and durability in alkaline electrolyte. Particularly, an extremely low overpotential of 40 mV is needed to generate hydrogen. Density functional theory calculation revealed that the formation of Ni-Mo2C Mott/NC Schottky interfaces enables favorable electronic structures for electrocatalytic water splitting. Besides, 3D hierarchical structure provides exposed active sites, facilitates mass and charge transfer, graphitic shells enhance stability. A symmetric electrolyzer using Ni-Mo2C/NC@NF generates 10 mA cm-2 at 1.59 V and operates steadily for 150 h, which even outperforms the noble metal couple, Pt/C//RuO2 for water electrolysis. The scalability, activity and durability renders Ni-Mo2C/NC@NF potential industrial application. Reference 1. M. Walter, N. Lewis et al, Chem. Rev. 2010, 110, 11, 6446. 2. M. Miao, B. Y. Xia, X. Wang et al, Chem. Eur. J. 2017, 23, 10947. 3. F. Yu, Y. Li et al Nanoscale, 2018,10, 6080. 4. H. Sun, F. Cheng., J. Chen et al. Adv. Mater. 2020, 32, 1806326. 5. Z. Xu, S. Jin, M. H. Seo, X. Wang, Appl. Catal. B: Environ. 2021, 292, 120168

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