Articles de revues : « Nanocrystal Design - Core-shell Heterostructure »

1

Nobile, Concetta, et Pantaleo Davide Cozzoli. « Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials ». Nanomaterials 12, n^o 10 (18 mai 2022) : 1729. http://dx.doi.org/10.3390/nano12101729.

Texte intégral

Résumé :

Composite inorganic nanoarchitectures, based on combinations of distinct materials, represent advanced solid-state constructs, where coexistence and synergistic interactions among nonhomologous optical, magnetic, chemical, and catalytic properties lay a basis for the engineering of enhanced or even unconventional functionalities. Such systems thus hold relevance for both theoretical and applied nanotechnology-based research in diverse areas, spanning optics, electronics, energy management, (photo)catalysis, biomedicine, and environmental remediation. Wet-chemical colloidal synthetic techniques have now been refined to the point of allowing the fabrication of solution free-standing and easily processable multicomponent nanocrystals with sophisticated modular heterostructure, built upon a programmed spatial distribution of the crystal phase, composition, and anchored surface moieties. Such last-generation breeds of nanocrystals are thus composed of nanoscale domains of different materials, assembled controllably into core/shell or heteromer-type configurations through bonding epitaxial heterojunctions. This review offers a critical overview of achievements made in the design and synthetic elaboration of colloidal nanocrystal heterostructures based on diverse associations of transition metals (with emphasis on plasmonic metals) and transition-metal oxides. Synthetic strategies, all leveraging on the basic seed-mediated approach, are described and discussed with reference to the most credited mechanisms underpinning regioselective heteroepitaxial deposition. The unique properties and advanced applications allowed by such brand-new nanomaterials are also mentioned.

Styles APA, Harvard, Vancouver, ISO, etc.

2

Paul, Sumana, Sirshendu Ghosh, Manas Saha et S. K. De. « Enhanced photophysical properties of plasmonic magnetic metal-alloyed semiconductor heterostructure nanocrystals : a case study for the Ag@Ni/Zn1−xMgxO system ». Physical Chemistry Chemical Physics 18, n^o 18 (2016) : 13092–107. http://dx.doi.org/10.1039/c6cp00375c.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

3

Wang, Xuejing, Yung-Chen Lin, Chia-Tse Tai, Seok Woo Lee, Tzu-Ming Lu, Sun Hae Ra Shin, Sadhvikas J. Addamane et al. « Formation of tubular conduction channel in a SiGe(P)/Si core/shell nanowire heterostructure ». APL Materials 10, n^o 11 (1 novembre 2022) : 111108. http://dx.doi.org/10.1063/5.0119654.

Texte intégral

Résumé :

Realizing a tubular conduction channel within a one-dimensional core–shell nanowire (NW) enables better understanding of quantum phenomena and exploration of electronic device applications. Herein, we report the growth of a SiGe(P)/Si core/shell NW heterostructure using a chemical vapor deposition coupled with vapor–liquid–solid growth mechanism. The entire NW heterostructure behaves as a p-type semiconductor, which demonstrates that the high-density carriers are confined within the 4 nm-thick Si shell and form a tubular conduction channel. These findings are confirmed by both calculations and the gate-dependent current–voltage ( I d– V g) characteristics. Atomic resolution microscopic analyses suggest a coherent epitaxial core/shell interface where strain is released by forming dislocations along the axial direction of the NW heterostructure. Additional surface passivation achieved via growing a SiGe(P)/Si/SiGe core/multishell NW heterostructure suggests potential strategies to enhance the tubular carrier density, which could be further modified by improving multishell crystallinity and structural design.

Styles APA, Harvard, Vancouver, ISO, etc.

4

Han, Chuang, Shao-Hai Li, Zi-Rong Tang et Yi-Jun Xu. « Tunable plasmonic core–shell heterostructure design for broadband light driven catalysis ». Chemical Science 9, n^o 48 (2018) : 8914–22. http://dx.doi.org/10.1039/c8sc04479a.

Texte intégral

Résumé :

A tunable core–shell heterostructure design coupling two conceptually different optical absorption models for improved broadband light absorption and hot charge carrier separation toward plasmon-mediated photocatalysis.

Styles APA, Harvard, Vancouver, ISO, etc.

5

Ünlü, Hilmi. « A thermoelastic model for strain effects on bandgaps and band offsets in heterostructure core/shell quantum dots ». European Physical Journal Applied Physics 86, n^o 3 (juin 2019) : 30401. http://dx.doi.org/10.1051/epjap/2019180350.

Texte intégral

Résumé :

A thermoelastic model is proposed to determine elastic strain effects on electronic properties of spherical Type I and Type II heterostructure core/shell quantum dots (QDs) as a function of dimensions of constituent semiconductors at any temperature. Proposed model takes into account the difference between lattice constants, linear expansion coefficients and anisotropy of elastic moduli (Young's modulus and Poisson's ratio) of constituent semiconductors, respectively. In analogous to lattice mismatch, we introduce so called the elastic anisotropy mismatch in heterostructures. Compressive strain acting on core (shell) side of heterointerfaces in CdSe/CdS, CdSe/ZnS, and ZnSe/ZnS QDs increases (decreases) as shell diameter is increased, which causes increase (decrease) in core bandgap as sell (core) diameter is increased in these nanostructures. Furthermore, there is a parabolic increase in conduction band offsets and core bandgaps in CdSe/CdS, CdSe/ZnS, and ZnSe/ZnS QDs and decrease in conduction band offset and core bandgap of ZnSe/CdS QD as core (shell) diameter increases for fixed shell (core) diameter. Comparison shows that using isotropic elastic moduli in determining band offsets and core band gaps gives better agreement with experiment than anisotropic elastic moduli for core bandgaps of CdSe/CdS, CdSe/ZnS, ZnSe/ZnS, and ZnSe/CdS core/shell QDs. Furthermore, we also show that the strain-modified two band effective mass approximation can be used to determine band offsets by using measured core band gaps in core/shell heterostructure QDs with Type II interface band alignment. Excellent agreement between predicted and measured core bandgaps in CdSe and ZnSe based core/shell QDs suggests that proposed model can be a good design tool for process simulation of core/shell heterostructure QDs.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Pelicano, Christian Mark, Itaru Raifuku, Yasuaki Ishikawa, Yukiharu Uraoka et Hisao Yanagi. « Hierarchical core–shell heterostructure of H2O-oxidized ZnO nanorod@Mg-doped ZnO nanoparticle for solar cell applications ». Materials Advances 1, n^o 5 (2020) : 1253–61. http://dx.doi.org/10.1039/d0ma00313a.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

7

Zhao, Yichen, Abhilash Sugunan, Qin Wang, Xuran Yang, David B. Rihtnesberg et Muhammet S. Toprak. « Direct Determination of Spatial Localization of Carriers in CdSe-CdS Quantum Dots ». Journal of Nanomaterials 2015 (2015) : 1–7. http://dx.doi.org/10.1155/2015/321354.

Texte intégral

Résumé :

Colloidal quantum dots (QDs) have gained significant attention due to their tunable band gap, simple solution processability, ease of scale-up, and low cost. By carefully choosing the materials, core-shell heterostructure QDs (HQDs) can be further synthesized with a controlled spatial spread of wave functions of the excited electrons and holes for various applications. Many investigations have been done to understand the exciton dynamics by optical characterizations. However, these spectroscopic data demonstrate that the spatial separation of the excitons cannot distinguish the distribution of excited electrons and holes. In this work, we report a simple and direct method to determine the localized holes and delocalized electrons in HQDs. The quasi-type-II CdSe-CdS core-shell QDs were synthesized via a thermolysis method. Poly(3-hexylthiophene) (P3HT) nanofiber and ZnO nanorods were selected as hole and electron conductor materials, respectively, and were combined with HQDs to form two different nanocomposites. Photoelectrical properties were evaluated under different environments via a quick and facile characterization method, confirming that the electrons in the HQDs were freely accessible at the surface of the nanocrystal, while the holes were confined within the CdSe core.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Kim, Whi Dong, Sooho Lee, Chaewon Pak, Ju Young Woo, Kangha Lee, Fábio Baum, Jonghan Won et Doh C. Lee. « Metal tips on pyramid-shaped PbSe/CdSe/CdS heterostructure nanocrystal photocatalysts : study of Ostwald ripening and core/shell formation ». Chemical Communications 50, n^o 14 (2014) : 1719. http://dx.doi.org/10.1039/c3cc48919a.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

9

Guo, Yating, Feng Gao, Pan Huang, Rong Wu, Wanying Gu, Jing Wei, Fangze Liu et Hongbo Li. « Light-Emitting Diodes Based on Two-Dimensional Nanoplatelets ». Energy Material Advances 2022 (7 février 2022) : 1–24. http://dx.doi.org/10.34133/2022/9857943.

Texte intégral

Résumé :

Colloidal semiconductor nanocrystals (NCs) attract significant interest in recent years due to their narrow and tunable emission wavelength in the visible range, as well as high photoluminescence quantum yield (PLQY), which are highly desired in display technologies. The high-quality NCs have been recognized as vital luminescent materials in realizing next-generation display devices. With further development, NCs with near-unity PLQY have been successfully synthesized through engineering of the core/shell heterostructure. However, as the external quantum efficiency (EQE) of the nanocrystal light-emitting diodes (LEDs) approaches the theoretical limit of about 20%, the low out-coupling factor proposes a challenge of enhancing the performance of a device when using the spherical QDs. Hence, the anisotropic NCs like nanoplatelets (NPLs) are proposed as promising solutions to improve the performance of nanocrystal LEDs. In this review, we will summarize the synthetic strategies of two-dimensional (2D) NPLs at first. Then, we will introduce fundamental concepts of LEDs, the main approaches to realize LEDs based on nanoplatelets, and the recent progress. Finally, the challenges and opportunities of LEDs based on anisotropic NCs are also presented.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Nasser, Ramzi, Xiao-Lu Wang, Jian Tiantian, Habib Elhouichet et Ji-Ming Song. « Hydrothermal design of CoMoO4@CoWO4 core-shell heterostructure for flexible all-solid-state asymmetric supercapacitors ». Journal of Energy Storage 51 (juillet 2022) : 104349. http://dx.doi.org/10.1016/j.est.2022.104349.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

Sisman, Orhan, Dario Zappa, Valentin-Adrian Maraloiu et Elisabetta Comini. « Fabrication of CuO (p)–ZnO (n) Core–Shell Nanowires and Their H2-Sensing Properties ». Materials 16, n^o 13 (3 juillet 2023) : 4802. http://dx.doi.org/10.3390/ma16134802.

Texte intégral

Résumé :

Unlike the conventional one-dimensional (1D) core–shell nanowires (NWs) composed of p-type shells and n-type cores, in this work, an inverse design is proposed by depositing n-type ZnO (shell) layers on the surface of p-type CuO (core) NWs, to have a comprehensive understanding of their conductometric gas-sensing kinetics. The surface morphologies of bare and core–shell NWs were investigated by field emission scanning electron microscope (FE-SEM). The ZnO shell layer was presented by overlay images taken by electron dispersive X-ray spectroscopy (EDX) and high-resolution transmission electron microscopy (HRTEM). The pronounced crystalline plane peaks of ZnO were recorded in the compared glancing incident X-ray diffraction (GI-XRD) spectra of CuO and CuO–ZnO core–shell NWs. The ZnO shell layers broaden the absorption curve of CuO NWs in the UV-vis absorption spectra. As a result of the heterostructure formation, the intrinsic p-type sensing behavior of CuO NWs towards 250 and 500 ppm of hydrogen (H2) switched to n-type due to the deposition of ZnO shell layers, at 400 °C in dry airflow.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Li, Feng, Xing Gao, Rui Wang, Tong Zhang, Geyu Lu et Nicolae Barsan. « Design of Core–Shell Heterostructure Nanofibers with Different Work Function and Their Sensing Properties to Trimethylamine ». ACS Applied Materials & ; Interfaces 8, n^o 30 (22 juillet 2016) : 19799–806. http://dx.doi.org/10.1021/acsami.6b04063.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

13

Ying, Liangri, Han Zhu, Huilin Li, Zhenfeng Zhu, Shuhui Sun, Xiaofan Wang, Shuanglong Lu et Mingliang Du. « Heterostructure design of Cu2O/Cu2S core/shell nanowires for solar-driven photothermal water vaporization towards desalination ». Sustainable Energy & ; Fuels 4, n^o 12 (2020) : 6023–29. http://dx.doi.org/10.1039/d0se00914h.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

14

Tang, Shin-Yi, Teng-Yu Su, Tzu-Yi Yang et Yu-Lun Chueh. « Novel Design of 0D Nanoparticles-2D Transition-Metal Dichalcogenides Heterostructured Devices for High-Performance Optical and Gas-Sensing Applications ». ECS Meeting Abstracts MA2022-02, n^o 36 (9 octobre 2022) : 1318. http://dx.doi.org/10.1149/ma2022-02361318mtgabs.

Texte intégral

Résumé :

Two-dimensional Transition metal dichalcogenides (TMDCs), have now attracted much attention due to their unique layered structure and physical properties. Up to date, several studies have demonstrated monolayered and few-layered TMDC-based photodetectors with good stability, photo-switching time and broadband detectivity from UV to infrared light region. However, the reported responsivity is not as high as the theoretical expectation, indicating that the light absorption is limited by the atomic thickness of 2D-TMDCs and could still be improved. To overcome the drawback of low absorption in 2D TMDC materials, previous reports have revealed several strategies to enhance the electric field and light-harvesting in these atomically thin TMDC layers by hybridizing plasmonic noble-metal nanoparticles, such as Pt, Au and Ag, to facilitate the light-matter interaction at the surface of semiconductors. In this regard, we aim to combine highly absorptive CuInS2(CIS) nanocrystals with noble metal nanoparticles as the photosensitizer to enhance the intrinsic absorptivity and promote the performance of MoS2-based photodetectors. The interests of noble nanocrystals such as platinum and gold are featured for their distinctive properties of the carrier transportation and the storage when combined with semiconductor materials. The strategy described here acts as a perspective to signiﬁcantly improve the performance of MoS2-based photodetectors with outstanding detection responsivity with selectable wavelengths by further controlling the size and material of the decorated CIS nanocrystals. In addition to optical sensing, TMDCs have also been developed as a promising candidate for gas-molecule detection. Different from commercial metal oxide gas sensors, TMDCs as sensing materials can be operated at room temperature with good performance, increasing its reliability for future industrial applications. Nevertheless, the relatively low response and long response/recovery time are the main drawbacks of these promising devices. Therefore, we proposed the approach to successfully increase the surface area of TMDCs by a one-step synthesis from WO3 into three-dimensional (3D) WS2 nanowalls through a rapid heating and rapid cooling process. Moreover, the combination of CdS/ZnS or CdSe/ZnS core/shell quantum dots (QDs) with different emission wavelengths and WS2 nanowalls will further improve the performance of WS2-based photodetector devices, including 3.5~4.7 times photocurrent enhancement and shorter response time. The remarkable results of the QD-WS2 hybrid devices to the high non-radiative energy transfer (NRET) efficiency between QDs and our nanostructured material are caused by the spectral overlap between the emission of QDs as the donors and the absorption of WS2 as the acceptors. Additionally, the outstanding NO2 gas-sensing properties of QDs/WS2 devices were demonstrated with a remarkably low detection limit down to 50 ppb with a fast response time of 26.8 s, contributed by tremendous local p-n junctions generated from p-type WS2 nanowalls and n-type CdSe-ZnS QDs in this hybrid system. Our strategies to combine 0D nanoparticles or quantum dots and 2D TMDC materials can significantly enhance the optical sensing and gas molecule sensing properties compared to pristine TMDC-based devices, resulting from the efficient charge or energy transfer between the multi-dimension material system and the creation of local p-n junctions. Moreover, the scalability of these hybrid nanostructures allows our devices to exhibit much more possibilities in advanced multifunctional applications.

Styles APA, Harvard, Vancouver, ISO, etc.

15

Liang, Haoyan, Tiesong Lin, Shengyao Wang, Henan Jia, Chun Li, Jian Cao, Jicai Feng, Weidong Fei et Junlei Qi. « A free-standing manganese cobalt sulfide@cobalt nickel layered double hydroxide core–shell heterostructure for an asymmetric supercapacitor ». Dalton Transactions 49, n^o 1 (2020) : 196–202. http://dx.doi.org/10.1039/c9dt03974k.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

16

Wu, Wenling, Chengwei Wang, Chunhui Zhao, Lei Wang, Jianfeng Zhu et Youlong Xu. « Rational design of hierarchical FeCo2O4 nanosheets@NiO nanowhiskers core-shell heterostructure as binder-free electrodes for efficient pseudocapacitors ». Electrochimica Acta 370 (février 2021) : 137789. http://dx.doi.org/10.1016/j.electacta.2021.137789.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

17

Liang, Shuting, Chaowei Wang, Fengjiao Li et Gang Song. « Supported Cu/W/Mo/Ni—Liquid Metal Catalyst with Core-Shell Structure for Photocatalytic Degradation ». Catalysts 11, n^o 11 (22 novembre 2021) : 1419. http://dx.doi.org/10.3390/catal11111419.

Texte intégral

Résumé :

Room-temperature liquid metal is a very ideal material for the design of catalytic materials. At low temperatures, the liquid metal enters the liquid state. It provides an opportunity to utilize the liquid phase in the catalysis, which is far superior to the traditional solid-phase catalyst. Aiming at the low performance and narrow application scope of the existing single-phase liquid metal catalyst, this paper proposed a type of liquid metal/metal oxide core-shell composite multi-metal catalyst. The Ga2O3 core-shell heterostructure was formed by chemical modification of liquid metals with different nano metals Cu/W/Mo/Ni, and it was applied to photocatalytic degrading organic contaminated raw liquor. The effects of different metal species on the rate of catalytic degradation were explored. The selectivity and stability of the LM/MO core-shell composite catalytic material were clarified, and it was found that the Ni-LM catalyst could degrade methylene blue and Congo red by 92% and 79%, respectively. The catalytic mechanism and charge transfer mechanism were revealed by combining the optical band gap value. Finally, we provided a theoretical basis for the further development of liquid metal photocatalytic materials in the field of new energy environments.

Styles APA, Harvard, Vancouver, ISO, etc.

18

Shabani, Farzan, Hamed Dehghanpour Baruj, Iklim Yurdakul, Savas Delikanli, Negar Gheshlaghi, Furkan Isik, Baiquan Liu, Yemliha Altintas, Betül Canımkurbey et Hilmi Volkan Demir. « Deep‐Red‐Emitting Colloidal Quantum Well Light‐Emitting Diodes Enabled through a Complex Design of Core/Crown/Double Shell Heterostructure ». Small 18, n^o 8 (10 décembre 2021) : 2106115. http://dx.doi.org/10.1002/smll.202106115.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

19

Li, Zhiliang, Shuqi Zheng, Ting Huang, Yuzhuo Zhang, Renyuan Teng et Guiwu Lu. « Rational design, high-yield synthesis, and low thermal conductivity of Te/Bi 2 Te 3 core/shell heterostructure nanotube composites ». Journal of Alloys and Compounds 617 (décembre 2014) : 247–52. http://dx.doi.org/10.1016/j.jallcom.2014.08.010.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

20

Xiao, Fang-Xing, Jianwei Miao et Bin Liu. « Self-assembly of aligned rutile@anatase TiO2nanorod@CdS quantum dots ternary core–shell heterostructure : cascade electron transfer by interfacial design ». Mater. Horiz. 1, n^o 2 (2014) : 259–63. http://dx.doi.org/10.1039/c3mh00097d.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

21

Xin, Fengxia, Hui Zhou, Qiyue Yin, Yong Shi, Fredrick Omenya, Guangwen Zhou et M. Stanley Whittingham. « Nanocrystal Conversion-Assisted Design of Sn–Fe Alloy with a Core–Shell Structure as High-Performance Anodes for Lithium-Ion Batteries ». ACS Omega 4, n^o 3 (5 mars 2019) : 4888–95. http://dx.doi.org/10.1021/acsomega.8b03637.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

22

Wu, Di, Jun Guo, Zhen-Hua Ge et Jing Feng. « Facile Synthesis Bi2Te3 Based Nanocomposites : Strategies for Enhancing Charge Carrier Separation to Improve Photocatalytic Activity ». Nanomaterials 11, n^o 12 (14 décembre 2021) : 3390. http://dx.doi.org/10.3390/nano11123390.

Texte intégral

Résumé :

Varying structure Bi2Te3-based nanocomposite powders including pure Bi2Te3, Bi2Te3/Bi core−shell, and Bi2Te3/AgBiTe2 heterostructure were synthesized by hydrothermal synthesis using Bi2S3 as the template and hydrazine as the reductant. Successful realization of Bi2Te3-based nanostructures were concluded from XRD, FESEM, and TEM. In this work, the improvement in the performance of the rhodamine B (RhB) decomposition efficiency under visible light was discussed. The Bi2Te3/AgBiTe2 heterostructures revealed propitious photocatalytic performance ca. 90% after 60 min. The performance was over Bi2Te3/Bi core-shell nanostructures (ca. 40%) and more, exceeding pure Bi2Te3 (ca. 5%). The reason could be scrutinized in terms of the heterojunction structure, improving the interfacial contact between Bi2Te3 and AgBiTe2 and enabling retardation in the recombination rate of the photogenerated charge carriers. A credible mechanism of the charge transfer process in the Bi2Te3/AgBiTe2 heterostructures for the decomposition of an aqueous solution of RhB was also explicated. In addition, this work also investigated the stability and recyclability of a Bi2Te3/AgBiTe2 heterojunction nanostructure photocatalyst. In addition, this paper anticipates that the results possess broad potential in the photocatalysis field for the design of a visible light functional and reusable heterojunction nanostructure photocatalyst.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Guo, Jiabin, Qichong Zhang, Qiulong Li, Juan Sun, Chaowei Li, Bing He, Zhenyu Zhou, Liyan Xie, Mingxing Li et Yagang Yao. « Rational Design of Hierarchical Titanium Nitride@Vanadium Pentoxide Core–Shell Heterostructure Fibrous Electrodes for High-Performance 1.6 V Nonpolarity Wearable Supercapacitors ». ACS Applied Materials & ; Interfaces 10, n^o 35 (14 août 2018) : 29705–11. http://dx.doi.org/10.1021/acsami.8b11997.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

24

Wang, Zhe, Bo Dai, Xiaohan Tang, Zhihui Che, Fei Hu, Chengying Shen, Wei Wu, Baode Shen et Hailong Yuan. « Fabrication and In Vitro/Vivo Evaluation of Drug Nanocrystals Self-Stabilized Pickering Emulsion for Oral Delivery of Quercetin ». Pharmaceutics 14, n^o 5 (20 avril 2022) : 897. http://dx.doi.org/10.3390/pharmaceutics14050897.

Texte intégral

Résumé :

The aim of this study was to develop a new drug nanocrystals self-stabilized Pickering emulsion (NSSPE) for improving oral bioavailability of quercetin (QT). Quercetin nanocrystal (QT–NC) was fabricated by high pressure homogenization method, and QT–NSSPE was then prepared by ultrasound method with QT–NC as solid particle stabilizer and optimized by Box-Behnken design. The optimized QT–NSSPE was characterized by fluorescence microscope (FM), scanning electron micrograph (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The stability, in vitro release, and in vivo oral bioavailability of QT–NSSPE were also investigated. Results showed that the droplets of QT–NSSPE with the size of 10.29 ± 0.44 μm exhibited a core-shell structure consisting of a core of oil and a shell of QT–NC. QT–NSSPE has shown a great stability in droplets shape, size, creaming index, zeta potential, and QT content during 30 days storage at 4, 25, and 40 °C. In vitro release studies showed that QT–NSSPE performed a better dissolution behavior (65.88% within 24 h) as compared to QT–NC (50.71%) and QT coarse powder (20.15%). After oral administration, the AUC0–t of QT–NSSPE was increased by 2.76-times and 1.38 times compared with QT coarse powder and QT–NC. It could be concluded that NSSPE is a promising oral delivery system for improving the oral bioavailability of QT.

Styles APA, Harvard, Vancouver, ISO, etc.

25

Lu, Longgang, Bin Zhang, Juanjuan Song, Haiwen Gao, Zongdeng Wu, Honglong Shen, Yujunwen Li, Wu Lei et Qingli Hao. « Synthesis of MnO–Sn cubes embedding in nitrogen-doped carbon nanofibers with high lithium-ion storage performance ». Nanotechnology 33, n^o 11 (23 décembre 2021) : 115403. http://dx.doi.org/10.1088/1361-6528/ac4064.

Texte intégral

Résumé :

Abstract In this paper, a carbon nanofiber (CNF) hybrid nanomaterial composed of MnO–Sn cubes embedding in nitrogen-doped CNF (MnO–Sn@CNF) is synthesized through electrospinning and post-thermal reduction processes. It exhibits good electrochemical lithium-ion storage performance as the anode, such as high reversible capacity, outstanding cycle performance (754 mAh g−1 at 1 A g−1 after 1000 cycles), and good rate capability (447 mAh g−1 at 5 A g−1). The excellent electrochemical properties are derived from a unique nanostructure design. MnO–Sn@CNF has a three-dimensional conductive network with a stable core–shell structure, which improves the electrical conductivity and mechanical stability of the materials. In addition, the mesopores on the surface of carbon fibers can shorten the diffusion distance of lithium ions and promote the combination of active sites of the material with lithium ions. The internal MnO and Sn form a heterostructure, which enhances the stability of the physical structure of the electrode material. This material design method provides a reference strategy for the development of high-performance lithium-ion batteries anode.

Styles APA, Harvard, Vancouver, ISO, etc.

26

Pan, Jing, Shaobin Li, Fengbo Li, Wenzhi Zhang, Dongxuan Guo, Li Zhang, Deqing Zhang, Hong Pan, Yushu Zhang et Yifeng Ruan. « Design and construction of core-shell heterostructure of Ni-V layered double hydroxide composite electrode materials for high-performance hybrid supercapacitor and L-Tryptophan sensor ». Journal of Alloys and Compounds 890 (janvier 2022) : 161781. http://dx.doi.org/10.1016/j.jallcom.2021.161781.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

27

Zhang, Jifen, Yanhua Wang, Jirui Wang et Tao Yi. « A Novel Solid Nanocrystals Self-Stabilized Pickering Emulsion Prepared by Spray-Drying with Hydroxypropyl-β-cyclodextrin as Carriers ». Molecules 26, n^o 6 (23 mars 2021) : 1809. http://dx.doi.org/10.3390/molecules26061809.

Texte intégral

Résumé :

A drug nanocrystals self-stabilized Pickering emulsion (NSSPE) with a unique composition and microstructure has been proven to significantly increase the bioavailability of poorly soluble drugs. This study aimed to develop a new solid NSSPE of puerarin preserving the original microstructure of NSSPE by spray-drying. A series of water-soluble solid carriers were compared and then Box-Behnken design was used to optimize the parameters of spray-drying. The drug release and stability of the optimized solid NSSPE in vitro were also investigated. The results showed that hydroxypropyl-β-cyclodextrin (HP-β-CD), rather than solid carriers commonly used in solidification of traditional Pickering emulsions, was suitable for the solid NSSPE to retain the original appearance and size of emulsion droplets after reconstitution. The amount of HP-β-CD had more influences on the solid NSSPE than the feed rate and the inlet air temperature. Fluorescence microscopy, confocal laser scanning microscopy and scanning electron microscopy showed that the reconstituted emulsion of the solid NSSPE prepared with HP-β-CD had the same core-shell structure with a core of oil and a shell of puerarin nanocrystals as the liquid NSSPE. The particle size of puerarin nanocrystal sand interfacial adsorption rate also did not change significantly. The cumulative amount of released puerarin from the solid NSSPE had no significant difference compared with the liquid NSSPE, which were both significantly higher than that of puerarin crude material. The solid NSSPE was stable for 3 months under the accelerated condition of 75% relative humidity and 40 °C. Thus, it is possible todevelop the solid NSSPE preserving the unique microstructure and the superior properties in vitro of the liquid NSSPE for poorly soluble drugs.

Styles APA, Harvard, Vancouver, ISO, etc.

28

Kim, Sung-Un, et Yong-Ho Ra. « Modeling and Epitaxial Growth of Homogeneous Long-InGaN Nanowire Structures ». Nanomaterials 11, n^o 1 (23 décembre 2020) : 9. http://dx.doi.org/10.3390/nano11010009.

Texte intégral

Résumé :

One-dimensional nanowires based on Group III-nitride materials are emerging as one of the most promising structures for applications of light-emitting diodes (LEDs), laser diodes (LDs), solar cells, and photocatalysts. However, leading to the so-called “green gap” in photonics, the fabrication of high concentration indium gallium nitride (InGaN) and long-InGaN structures remains still challenging. In this study, we performed simulations for structural modeling of uniform temperature distribution in a nanowire epitaxy, and have successfully developed high-concentration InGaN and long-InGaN nanowire heterostructures on silicon (Si) substrate using molecular beam epitaxy (MBE) system. From scanning electron microscope (SEM) and transmission electron microscope (TEM) results, it was confirmed that the various doped-InGaN nanowire structures show much higher crystal quality compared to conventional nanowire structures. By introducing a new three-step modulated growth technique, the n-/p-InGaN active regions were greatly increased and the optical properties were also dramatically improved due to reduced phase separation. In addition, a multi-band p-InGaN/GaN heterostructure was successfully fabricated with the core–shell nanowire structures, which enable the emission of light in the entire visible spectral range, and protect the InGaN surface from surface recombination. This paper offers important insight into the design and epitaxial growth of InGaN nanowire heterostructures.

Styles APA, Harvard, Vancouver, ISO, etc.

29

Matysiak, Wiktor, Tomasz Tański et Weronika Monika Smok. « Morphology and structure characterization of crystalline SnO2 1D nanostructures ». Photonics Letters of Poland 12, n^o 3 (30 septembre 2020) : 70. http://dx.doi.org/10.4302/plp.v12i3.1019.

Texte intégral

Résumé :

In recent years, many attempts have been made to improve the sensory properties of SnO2, including design of sensors based on one-dimensional nanostructures of this material, such as nanofibers, nanotubes or nanowires. One of the simpler methods of producing one-dimensional tin oxide nanomaterials is to combine the electrospinning method with a sol-gel process. The purpose of this work was to produce SnO2 nanowires using a hybrid electrospinning method combined with a heat treatment process at the temperature of 600 °C and to analyze the morphology and structure of the one-dimensional nanomaterial produced in this way. Analysis of the morphology of composite one-dimensional tin oxide nanostructures showed that smooth, homogeneous and crystalline nanowires were obtained. Full Text: PDF ReferencesN. Dharmaraj, C.H. Kim, K.W. Kim, H.Y. Kim, E.K. Suh, "Spectral studies of SnO2 nanofibres prepared by electrospinning method", Spectrochim. Acta - Part A Mol. Biomol. Spectrosc. 64, (2006) CrossRef N. Gao, H.Y. Li, W. Zhang, Y. Zhang, Y. Zeng, H. Zhixiang, ... & H. Liu, "QCM-based humidity sensor and sensing properties employing colloidal SnO2 nanowires", Sens. Actuators B Chem. 293, (2019), 129-135. CrossRef W. Ge, Y. Chang, V. Natarajan, Z. Feng, J. Zhan, X. Ma, "In2O3-SnO2 hybrid porous nanostructures delivering enhanced formaldehyde sensing performance", J.Alloys and Comp. 746, (2018) CrossRef M. Zhang, Y. Zhen, F. Sun, C. Xu, "Hydrothermally synthesized SnO2-graphene composites for H2 sensing at low operating temperature", Mater. Sci. Eng. B. 209, (2016), 37-44. CrossRef Y. Zhang, X. He, J. Li, Z. Miao, F. Huang, "Fabrication and ethanol-sensing properties of micro gas sensor based on electrospun SnO2 nanofibers", Sens. Actuators B Chem. 132, (2008), 67-73. CrossRef W.Q. Li, S.Y. Ma, J. Luo, Y.Z. Mao, L. Cheng, D.J. Gengzang, X.L. Xu, S H. Yan, "Synthesis of hollow SnO2 nanobelts and their application in acetone sensor", Mater. Lett. 132, (2014), 338-341. CrossRef E. Mudra, I. Shepa, O. Milkovic, Z. Dankova, A. Kovalcikova, A. Annusova, E. Majkova, J. Dusza, "Effect of iron doping on the properties of SnO2 nano/microfibers", Appl. Surf. Sci. 480, (2019), 876-881. CrossRef P. Mohanapriya, H. Segawa, K. Watanabe, K. Watanabe, S. Samitsu, T.S. Natarajan, N.V. Jaya, N. Ohashi, "Enhanced ethanol-gas sensing performance of Ce-doped SnO2 hollow nanofibers prepared by electrospinning", Sens. Actuators B Chem. 188, (2013), 872-878. CrossRef W.Q. Li, S.Y. Ma, Y.F. Li, X.B. Li, C.Y. Wang, X.H. Yang, L. Cheng, Y.Z. Mao, J. Luo, D.J. Gengzang, G.X. Wan, X.L. Xu, "Preparation of Pr-doped SnO2 hollow nanofibers by electrospinning method and their gas sensing properties", J.Alloys and Comp. 605, (2014), 80-88. CrossRef X.H. Xu, S.Y. Ma, X.L. Xu, T. Han, S.T. Pei, Y. Tie, P.F. Cao, W.W. Liu, B.J. Wang, R. Zhang, J.L. Zhang, "Ultra-sensitive glycol sensing performance with rapid-recovery based on heterostructured ZnO-SnO2 hollow nanotube", Mater. Lett, 273, (2020), 127967. CrossRef F. Li, X. Gao, R. Wang, T. Zhang, G. Lu, Sens. "Study on TiO2-SnO2 core-shell heterostructure nanofibers with different work function and its application in gas sensor", Actuators B Chem, 248, (2017), 812-819. CrossRef S. Bai, W. Guo, J. Sun, J. Li, Y. Tian, A. Chen, R. Luo, D. Li, "Synthesis of SnO2–CuO heterojunction using electrospinning and application in detecting of CO", Sens Actuators B Chem, 226, (2016), 96-103. CrossRef H. Du, P.J. Yao, Y. Sun, J. Wang, H. Wang, N. Yu, "Electrospinning Hetero-Nanofibers In2O3/SnO2 of Homotype Heterojunction with High Gas Sensing Activity", Sensors, 17, (2017), 1822. CrossRef X. Wang, H. Fan, P. Ren, "Electrospinning derived hollow SnO2 microtubes with highly photocatalytic property", Catal. Commun. 31, (2013), 37-41. CrossRef L. Cheng, S.Y. Ma, T.T. Wang, X.B. Li, J. Luo, W.Q. Li, Y.Z. Mao, D.J Gengzang, "Synthesis and characterization of SnO2 hollow nanofibers by electrospinning for ethanol sensing properties", Mater. Lett. 131, (2014), 23-26. CrossRef P.H. Phuoc, C.M. Hung, N.V. Toan, N.V. Duy, N.D. Hoa, N.V. Hieu, "One-step fabrication of SnO2 porous nanofiber gas sensors for sub-ppm H2S detection", Sens. Actuators A Phys. 303, (2020), 111722. CrossRef A.E. Deniz, H.A. Vural, B. Ortac, T. Uyar, "Gold nanoparticle/polymer nanofibrous composites by laser ablation and electrospinning", Matter. Lett. 65, (2011), 2941-2943. CrossRef S. Sagadevan, J. Podder, "Investigation on Structural, Surface Morphological and Dielectric Properties of Zn-doped SnO2 Nanoparticles", Mater. Res. 19, (2016), 420-425. CrossRef

Styles APA, Harvard, Vancouver, ISO, etc.

30

Frechette, Layne B., Christoph Dellago et Phillip L. Geissler. « Elastic forces drive nonequilibrium pattern formation in a model of nanocrystal ion exchange ». Proceedings of the National Academy of Sciences 118, n^o 52 (21 décembre 2021). http://dx.doi.org/10.1073/pnas.2114551118.

Texte intégral

Résumé :

Significance The widely used process of nanocrystal ion exchange operates out of thermodynamic equilibrium and can require mixing components of varying sizes. Here we use theory and computer simulation to study a simple model which captures these two basic features of ion exchange reactions. We show that a strong driving force for exchange among different-sized species creates nonequilibrium patterns within model nanocrystals. We further demonstrate that such patterns can be thermodynamically stable within core/shell nanocrystals. These results help us understand the heterostructures formed in ion-exchanged nanocrystals and suggest strategies for leveraging elasticity to design patterns in nanoscale materials.

Styles APA, Harvard, Vancouver, ISO, etc.

31

Zhuo, Ming-Peng, Guang-Peng He, Xue-Dong Wang et Liang-Sheng Liao. « Organic superstructure microwires with hierarchical spatial organisation ». Nature Communications 12, n^o 1 (15 avril 2021). http://dx.doi.org/10.1038/s41467-021-22513-5.

Texte intégral

Résumé :

AbstractRationally designing and precisely constructing the dimensions, configurations and compositions of organic nanomaterials are key issues in material chemistry. Nevertheless, the precise synthesis of organic heterostructure nanomaterials remains challenging owing to the difficulty of manipulating the homogeneous/heterogeneous-nucleation process and the complex epitaxial relationships of combinations of dissimilar materials. Herein, we propose a hierarchical epitaxial-growth approach with the combination of longitudinal and horizontal epitaxial-growth modes for the design and synthesis of a variety of organic superstructure microwires with accurate spatial organisation by regulating the heterogeneous-nucleation crystallisation process. The lattice-matched longitudinal and horizontal epitaxial-growth modes are separately employed to construct the primary organic core/shell and segmented heterostructure microwires. Significantly, these primary organic core/shell and segmented microwires are further applied to construct the core/shell-segmented and segmented-core/shell type’s organic superstructure microwires through the implementation of multiple spatial epitaxial-growth modes. This strategy can be generalised to all organic microwires with tailored multiple substructures, which affords an avenue to manipulate their physical/chemical features for various applications.

Styles APA, Harvard, Vancouver, ISO, etc.

32

Peng, Tao, Wei Guo, Yingge Zhang, Yangbo Wang, Kejia Zhu, Yan Guo, Yinghui Wang, Yang Lu et Hailong Yan. « The Core-Shell Heterostructure CNT@Li2FeSiO4@C as a Highly Stable Cathode Material for Lithium-Ion Batteries ». Nanoscale Research Letters 14, n^o 1 (17 octobre 2019). http://dx.doi.org/10.1186/s11671-019-3165-x.

Texte intégral

Résumé :

Abstract The reasonable design of nanostructure is the key to solving the inherent defects and realizing a high performance of Li2FeSiO4 cathode materials. In this work, a novel heterostructure CNT@Li2FeSiO4@C has been designed and synthesized and used as a cathode material for lithium-ion battery. It is revealed that the product has a uniform core-shell structure, and the thickness of the Li2FeSiO4 layer and the outer carbon layer is about 19 nm and 2 nm, respectively. The rational design effectively accelerates the diffusion of lithium ions, improves the electric conductivity, and relieves the volume change during the charging/discharging process. With the advantages of its specific structure, CNT@Li2FeSiO4@C has successfully overcome the inherent shortcomings of Li2FeSiO4 and shown good reversible capacity and cycle properties.

Styles APA, Harvard, Vancouver, ISO, etc.

33

Wang, Yan, Runrun Cheng, Wen-Gang Cui, Zhao Lu, Yaxiong Yang, Hongge Pan et Renchao Che. « Heterostructure Design Of 3d Hydrangea-Like Fe3o4/Fe7s8@C Core-Shell Composite As A High-Efficiency Microwave Absorber ». SSRN Electronic Journal, 2023. http://dx.doi.org/10.2139/ssrn.4363134.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

34

Wang, Yan, Runrun Cheng, Wen-Gang Cui, Zhao Lu, Yaxiong Yang, Hongge Pan et Renchao Che. « Heterostructure design of 3D hydrangea-like Fe3O4/Fe7S8@C core-shell composite as a high-efficiency microwave absorber ». Carbon, avril 2023, 118043. http://dx.doi.org/10.1016/j.carbon.2023.118043.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

35

Jiang, Nian, Hannah J. Joyce, Patrick Parkinson, Jennifer Wong-Leung, Hark Hoe Tan et Chennupati Jagadish. « Facet-Related Non-uniform Photoluminescence in Passivated GaAs Nanowires ». Frontiers in Chemistry 8 (7 décembre 2020). http://dx.doi.org/10.3389/fchem.2020.607481.

Texte intégral

Résumé :

The semiconductor nanowire architecture provides opportunities for non-planar electronics and optoelectronics arising from its unique geometry. This structure gives rise to a large surface area-to-volume ratio and therefore understanding the effect of nanowire surfaces on nanowire optoelectronic properties is necessary for engineering related devices. We present a systematic study of the non-uniform optical properties of Au-catalyzed GaAs/AlGaAs core–shell nanowires introduced by changes in the sidewall faceting. Significant variation in intra-wire photoluminescence (PL) intensity and PL lifetime (τPL) was observed along the nanowire axis, which was strongly correlated with the variation of sidewall facets from {112} to {110} from base to tip. Faster recombination occurred in the vicinity of {112}-oriented GaAs/AlGaAs interfaces. An alternative nanowire heterostructure, the radial quantum well tube consisting of a GaAs layer sandwiched between two AlGaAs barrier layers, is proposed and demonstrates superior uniformity of PL emission along the entire length of nanowires. The results emphasize the significance of nanowire facets and provide important insights for nanowire device design.

Styles APA, Harvard, Vancouver, ISO, etc.

36

Wang, Baoyuan, Bin Zhu, Sining Yun, Wei Zhang, Chen Xia, Muhammad Afzal, Yixiao Cai, Yanyan Liu, Yi Wang et Hao Wang. « Fast ionic conduction in semiconductor CeO2-δ electrolyte fuel cells ». NPG Asia Materials 11, n^o 1 (13 septembre 2019). http://dx.doi.org/10.1038/s41427-019-0152-8.

Texte intégral

Résumé :

Abstract Producing electrolytes with high ionic conductivity has been a critical challenge in the progressive development of solid oxide fuel cells (SOFCs) for practical applications. The conventional methodology uses the ion doping method to develop electrolyte materials, e.g., samarium-doped ceria (SDC) and yttrium-stabilized zirconia (YSZ), but challenges remain. In the present work, we introduce a logical design of non-stoichiometric CeO2-δ based on non-doped ceria with a focus on the surface properties of the particles. The CeO2−δ reached an ionic conductivity of 0.1 S/cm and was used as the electrolyte in a fuel cell, resulting in a remarkable power output of 660 mW/cm2 at 550 °C. Scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS) clearly clarified that a surface buried layer on the order of a few nanometers was composed of Ce3+ on ceria particles to form a CeO2−δ@CeO2 core–shell heterostructure. The oxygen deficient layer on the surface provided ionic transport pathways. Simultaneously, band energy alignment is proposed to address the short circuiting issue. This work provides a simple and feasible methodology beyond common structural (bulk) doping to produce sufficient ionic conductivity. This work also demonstrates a new approach to progress from material fundamentals to an advanced low-temperature SOFC technology.

Styles APA, Harvard, Vancouver, ISO, etc.

Articles de revues sur le sujet « Nanocrystal Design - Core-shell Heterostructure »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres