Journal articles: 'Mott-Schottky Catalyst'

1

Huang, Yuan, Haoting Yan, Chenyang Zhang, Yize Wang, Qinhong Wei, and Renkun Zhang. "Interfacial Electronic Effects in Co@N-Doped Carbon Shells Heterojunction Catalyst for Semi-Hydrogenation of Phenylacetylene." Nanomaterials 11, no. 11 (October 20, 2021): 2776. http://dx.doi.org/10.3390/nano11112776.

Full text

Abstract:

Metal-supported catalyst with high activity and relatively simple preparation method is given priority to industrial production. In this work, this study reported an easily accessible synthesis strategy to prepare Mott-Schottky-type N-doped carbon encapsulated metallic Co (Co@Np+gC) catalyst by high-temperature pyrolysis method in which carbon nitride (g-C3N4) and dopamine were used as support and nitrogen source. The prepared Co@Np+gC presented a Mott-Schottky effect; that is, a strong electronic interaction of metallic Co and N-doped carbon shell was constructed to lead to the generation of Mott-Schottky contact. The metallic Co, due to high work function as compared to that of N-doped carbon, transferred electrons to the N-doped outer shell, forming a new contact interface. In this interface area, the positive and negative charges were redistributed, and the catalytic hydrogenation mainly occurred in the area of active charges. The Co@Np+gC catalyst showed excellent catalytic activity in the hydrogenation of phenylacetylene to styrene, and the selectivity of styrene reached 82.4%, much higher than those of reference catalysts. The reason for the promoted semi-hydrogenation of phenylacetylene was attributed to the electron transfer of metallic Co, as it was caused by N doping on carbon.

APA, Harvard, Vancouver, ISO, and other styles

2

Ren, Yongwang, Huizhong Xu, Beibei Han, and Jing Xu. "Construction of N-Doped Carbon-Modified Ni/SiO2 Catalyst Promoting Cinnamaldehyde Selective Hydrogenation." Molecules 28, no. 10 (May 17, 2023): 4136. http://dx.doi.org/10.3390/molecules28104136.

Full text

Abstract:

At present, the selective hydrogenation of α, β-unsaturated aldehydes remains a challenge due to competition between unsaturated functional groups (C=C and C=O). In this study, N-doped carbon deposited on silica-supported nickel Mott–Schottky type catalysts (Ni/SiO2@NxC) was prepared for the selective hydrogenation of cinnamaldehyde (CAL) by using the respective hydrothermal method and high-temperature carbonization method. The prepared optimal Ni/SiO2@N7C catalyst achieved 98.9% conversion and 83.1% selectivity for 3-phenylpropionaldehyde (HCAL) in the selective hydrogenation reaction of CAL. By constructing the Mott–Schottky effect, the electron transfer from metallic Ni to N-doped carbon at their contact interface was promoted, and the electron transfer was demonstrated by XPS and UPS. Experimental results indicated that by modulating the electron density of metallic Ni, the catalytic hydrogenation of C=C bonds was preferentially performed to obtain higher HCAL selectivity. Meanwhile, this work also provides an effective way to design electronically adjustable type catalysts for more selective hydrogenation reactions.

APA, Harvard, Vancouver, ISO, and other styles

3

Zuraev, A. V., Y. V. Grigoriev, C. M. Verbilo, L. S. Ivashkevich, A. S. Lyakhov, and O. A. Ivashkevich. "PalladiumPolymer Nanocomposite: An Efficient Catalyst for Green Suzuki–Miyaura Cross-Coupling and Mott-Schottky Nitrobenzene Reduction Processes." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 55, no. 2 (June 29, 2019): 196–204. http://dx.doi.org/10.29235/1561-8331-2019-55-2-196-204.

Full text

Abstract:

A new catalyst for green Suzuki–Miyaura cross-coupling and Mott-Schottky nitrobenzene reduction processes was prepared by thermolysis of palladium (II) poly-5-vinyltetrazolate. Heterogeneous catalyst includes Pd-nanoparticles supported on polymeric matrix. It presents recoverable and recyclable catalyst and the catalyzed reactions proceed in aqueous media at room temperature in aerobic conditions.

APA, Harvard, Vancouver, ISO, and other styles

4

Sarkar, Bidushi, Debanjan Das, and Karuna Kar Nanda. "pH-dependent hydrogen evolution using spatially confined ruthenium on hollow N-doped carbon nanocages as a Mott–Schottky catalyst." Journal of Materials Chemistry A 9, no. 24 (2021): 13958–66. http://dx.doi.org/10.1039/d1ta02375f.

Full text

Abstract:

We demonstrate Ru nanoparticles confined on a N-doped hollow carbon matrix as a wide pH hydrogen evolution electrocatalyst. The formation of a Mott–Schottky heterojunction at the strongly coupled Ru/N-doped C interface enhances the catalysis.

APA, Harvard, Vancouver, ISO, and other styles

5

Xu, Zhixiao, and Xiaolei Wang. "Nickel-Molybdenum Carbide/Nitrogen-Doped Carbon Mott-Schottky Nanoarray for Water Spitting." ECS Meeting Abstracts MA2022-01, no. 55 (July 7, 2022): 2307. http://dx.doi.org/10.1149/ma2022-01552307mtgabs.

Full text

Abstract:

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

APA, Harvard, Vancouver, ISO, and other styles

6

Jiao, Zhifeng, Zhaoyang Zhai, Xiaoning Guo, and Xiang-Yun Guo. "Visible-Light-Driven Photocatalytic Suzuki–Miyaura Coupling Reaction on Mott–Schottky-type Pd/SiC Catalyst." Journal of Physical Chemistry C 119, no. 6 (February 3, 2015): 3238–43. http://dx.doi.org/10.1021/jp512567h.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Arifin, Md Noor, Kaykobad Md Rezaul Karim, Hamidah Abdullah, and Maksudur R. Khan. "Synthesis of Titania Doped Copper Ferrite Photocatalyst and Its Photoactivity towards Methylene Blue Degradation under Visible Light Irradiation." Bulletin of Chemical Reaction Engineering & Catalysis 14, no. 1 (April 15, 2019): 219. http://dx.doi.org/10.9767/bcrec.14.1.3616.219-227.

Full text

Abstract:

This paper reports the photocatalytic decomposition of methylene blue (MB) over titania doped copper ferrite, CuFe2O4/TiO2 with 50 wt% loading, synthesized via sol-gel method. The synthesized photocatalyst was characterized by X-ray diffraction, UV-vis diffuse reflectance, and photoluminescence, Mott-Schottky (MS) analysis and linear sweep voltammetry (LSV). The catalyst loadings were varied from 0.25 – 1.0 g/L and the optimum catalyst loading found to be 0.5 g/L. At the optimum loading, the conversion achieved was 83.7%. The other loadings produced slightly lower conversions at 82.7%, 80.6% and 80.0%, corresponding to 0.25, 1 and 0.75 g/L after 3 hours of irradiation. The study on the effect of initial concentration indicated that 20 ppm as the optimum concentration, tested with 0.5 g/L catalyst loading. The spent catalyst was used for the recyclability test and demonstrated a high longevity with a degradation efficiency less than 6 % for each time interval. The novelty of this study lies on the new application of photocatalytic material, CuFe2O4/TiO2 on thiazine dye that shows remarkable activity and reusability performance under visible light irradiation. Copyright © 2019 BCREC Group. All rights reservedReceived: 15th November 2018; Revised: 14th January 2019; Accepted: 17th January 2019; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Arifin, M.N., Karim, K.M.R., Abdullah, H., Khan, M.R. (2019). Synthesis of Titania Doped Copper Ferrite Photocatalyst and Its Photoactivity towards Methylene Blue Degradation under Visible Light Irradiation. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 219-227 (doi:10.9767/bcrec.14.1.3616.219-227) Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.3616.219-227

APA, Harvard, Vancouver, ISO, and other styles

8

Yan, Ruyu, Xinyi Liu, Haijie Zhang, Meng Ye, Zhenxing Wang, Jianjian Yi, Binxian Gu, and Qingsong Hu. "Carbon Quantum Dots Accelerating Surface Charge Transfer of 3D PbBiO2I Microspheres with Enhanced Broad Spectrum Photocatalytic Activity—Development and Mechanism Insight." Materials 16, no. 3 (January 27, 2023): 1111. http://dx.doi.org/10.3390/ma16031111.

Full text

Abstract:

The development of a highly efficient, visible-light responsive catalyst for environment purification has been a long-standing exploit, with obstacles to overcome, including inefficient capture of near-infrared photons, undesirable recombination of photo-generated carriers, and insufficient accessible reaction sites. Hence, novel carbon quantum dots (CQDs) modified PbBiO2I photocatalyst were synthesized for the first time through an in-situ ionic liquid-induced method. The bridging function of 1-butyl-3-methylimidazolium iodide ([Bmim]I) guarantees the even dispersion of CQDs around PbBiO2I surface, for synchronically overcoming the above drawbacks and markedly promoting the degradation efficiency of organic contaminants: (i) CQDs decoration harness solar photons in the near-infrared region; (ii) particular delocalized conjugated construction of CQDs strength via the utilization of photo-induced carriers; (iii) π–π interactions increase the contact between catalyst and organic molecules. Benefiting from these distinguished features, the optimized CQDs/PbBiO2I nanocomposite displays significantly enhanced photocatalytic performance towards the elimination of rhodamine B and ciprofloxacin under visible/near-infrared light irradiation. The spin-trapping ESR analysis demonstrates that CQDs modification can boost the concentration of reactive oxygen species (O2•−). Combined with radicals trapping tests, valence-band spectra, and Mott–Schottky results, a possible photocatalytic mechanism is proposed. This work establishes a significant milestone in constructing CQDs-modified, bismuth-based catalysts for solar energy conversion applications.

APA, Harvard, Vancouver, ISO, and other styles

9

Karim, Kaykobad Md Rezaul, Huei Ruey Ong, Hamidah Abdullah, Abu Yousuf, Chin Kui Cheng, and Mohd Maksudur Rahman Khan. "Electrochemical Study of Copper Ferrite as a Catalyst for CO2 Photoelectrochemical Reduction." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 2 (June 11, 2018): 236. http://dx.doi.org/10.9767/bcrec.13.2.1317.236-244.

Full text

Abstract:

In this work, p-type CuFe2O4 was synthesized by sol gel method. The prepared CuFe2O4 was used as photocathode catalyst for photoelectrochemical (PEC) CO2 reduction. The XRD, UV-Visible Spectroscopy (UV-Vis), and Mott-Schottky (MS) experiments were done to characterize the catalyst. Linear sweep voltammetry (LSV) was employed to evaluate the visible light (λ>400 nm) effect of this catalyst for CO2 reduction. The band gap energy of the catalyst was calculated from the UV-Vis and was found 1.30 eV. Flat band potential of the prepared CuFe2O4 was also calculated and found 0.27 V versus Ag/AgCl. Under light irradiation in the CO2-saturated NaHCO3 solution, a remarkable current development associated with CO2 reduction was found during LSV for the prepared electrode from onset potential -0.89 V with a peak current emerged at -1.01 V (vs Ag/AgCl) representing the occurrence of CO2 reduction reaction. In addition, the mechanism of PEC was proposed for the photocathode where the necessity of a bias potential in the range of 0.27 to ~ -1.0 V vs Ag/AgCl was identified which could effectively inhibit the electron-hole (e-/h+) recombination process leading to an enhancement of CO2 reduction reactions. Copyright © 2018 BCREC Group. All rights reservedReceived: 4th July 2017; Revised: 5th November 2017; Accepted: 15th November 2017; Available online: 11st June 2018; Published regularly: 1st August 2018How to Cite: Karim, K.M.R., Ong, H.R., Abdullah, H., Yousuf, A., Cheng, C.K., Khan, M.K.R. (2018). Electrochemical Study of Copper Ferrite as a Catalyst for CO2 Photoelectrochemical Reduction. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 236-244 (doi:10.9767/bcrec.13.2.1317.236-244)

APA, Harvard, Vancouver, ISO, and other styles

10

Zhang, Chaoqi, Ruifeng Du, Jordi Jacas Biendicho, Mingjie Yi, Ke Xiao, Dawei Yang, Ting Zhang, et al. "Tubular CoFeP@CN as a Mott–Schottky Catalyst with Multiple Adsorption Sites for Robust Lithium−Sulfur Batteries." Advanced Energy Materials 11, no. 24 (May 8, 2021): 2100432. http://dx.doi.org/10.1002/aenm.202100432.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Wang, Jiashi, Qinhong Wei, Qingxiang Ma, Zhongya Guo, Fangfang Qin, Zinfer R. Ismagilov, and Wenzhong Shen. "Constructing Co@N-doped graphene shell catalyst via Mott-Schottky effect for selective hydrogenation of 5-hydroxylmethylfurfural." Applied Catalysis B: Environmental 263 (April 2020): 118339. http://dx.doi.org/10.1016/j.apcatb.2019.118339.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Goel, Bharat, Ved Vyas, Nancy Tripathi, Ajit Kumar Singh, Prashanth W. Menezes, Arindam Indra, and Shreyans K. Jain. "Amidation of Aldehydes with Amines under Mild Conditions Using Metal‐Organic Framework Derived NiO@Ni Mott‐Schottky Catalyst." ChemCatChem 12, no. 22 (September 7, 2020): 5743–49. http://dx.doi.org/10.1002/cctc.202001041.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Jiang, Jing, Wei Wei, Zhen Ren, Yang Luo, Xinzhi Wang, Ying Xu, Mingming Chang, and Lunhong Ai. "Facile construction of robust Ru-Co3O4 Mott-Schottky catalyst enabling efficient dehydrogenation of ammonia borane for hydrogen generation." Journal of Colloid and Interface Science 646 (September 2023): 25–33. http://dx.doi.org/10.1016/j.jcis.2023.04.181.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Yang, Guangying, Cheng Pan, Haitao Yang, and Nianjie Feng. "Carbon-supported nickel catalyst prepared from steam-exploded poplar by recovering Ni(II)." BioResources 16, no. 3 (June 15, 2021): 5481–93. http://dx.doi.org/10.15376/biores.16.3.5481-5493.

Full text

Abstract:

Poplar pretreated by steam explosion was used as an adsorbent to simulate the adsorption process of nickel ion in wastewater. The result of kinetics suggested that the pseudo-second-order model was well suited to describing the adsorption of nickel ion. Through controlled adsorption, steam-exploded poplar was recycled after Ni2+ adsorption and then reduced to carbon-supported nickel catalyst (NiC700). Spectrum analyses of Fourier transform infrared spectrometry (FTIR), X-ray diffractometry (XRD), X-ray photoelectron spectrometry (XPS), Brunauer Emmett-Teller (BET) surface area, and electrochemical tests were applied to study the properties of the NiC700 relative to the control carbonized materials having no Ni (C700). The FTIR analysis revealed that there were chemical interactions and ion changes between OH, C–H, C=O, and heavy metal ions in the bio-adsorption process of nickel. The surface area of NiC700 was 1480 m2/g. The presence of Ni nanoparticles in NiC700 after reduction was confirmed by the XRD and XPS analyses. Electrochemical impedance spectroscopy (EIS), photocurrent (IT), and Mott Schottky curve results revealed that the conduction band potential of NiC700 (ECB, NiC700) was -0.10 eV vs. RHE (reversible hydrogen electrode) as an n-type semiconductor, and the Ni-doped carbon fiber exhibited certain electrophotocatalytic activity due to the nickel modification.

APA, Harvard, Vancouver, ISO, and other styles

15

Hernández, Rafael, José Rosendo Hernández-Reséndiz, Marisela Cruz-Ramírez, Rodrigo Velázquez-Castillo, Luis Escobar-Alarcón, Luis Ortiz-Frade, and Karen Esquivel. "Au-TiO2 Synthesized by a Microwave- and Sonochemistry-Assisted Sol-Gel Method: Characterization and Application as Photocatalyst." Catalysts 10, no. 9 (September 13, 2020): 1052. http://dx.doi.org/10.3390/catal10091052.

Full text

Abstract:

Titanium dioxide (TiO2) is a widely used and well studied photocatalyst synthesized using different methodologies, including sol-gel, which allows one to modify the material in a one-pot step. By using a microwave- and sonochemistry-assisted sol-gel method, x wt.% Au-TiO2 photocatalysts were successfully synthesized. Physicochemical characterization of the photocatalysts shows an average crystallite size of 10.5 nm and an even morphological distribution of spherical particles with the sonochemistry synthesis method. For the microwave method an average value of crystallite size of 8.3 nm was found and it presents an increase with the amount of Au load. The cyclic voltammetric response and Mott-Schottky analysis are consistent with a semiconductor material containing metallic particles and for a heterophase junction of anatase and brookite with oxygen vacancies, respectively. The photocatalytic activity was assessed by paracetamol degradation in an aqueous solution as model. The sonochemistry-synthesized photocatalysts display the most promising results as they have a better paracetamol removal and the amount of gold in the catalyst (0.7 wt.%) was found to be optimal for this process.

APA, Harvard, Vancouver, ISO, and other styles

16

Cheng, Saisai, Xufeng Meng, Ningzhao Shang, Shutao Gao, Cheng Feng, Chun Wang, and Zhi Wang. "Pd supported on g-C3N4 nanosheets: Mott–Schottky heterojunction catalyst for transfer hydrogenation of nitroarenes using formic acid as hydrogen source." New Journal of Chemistry 42, no. 3 (2018): 1771–78. http://dx.doi.org/10.1039/c7nj04268j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Tamiru Mengistu, Mintesinot, Tadele Hunde Wondimu, Dinsefa Mensur Andoshe, Jung Yong Kim, Osman Ahmed Zelekew, Fekadu Gashaw Hone, Newaymedhin Aberra Tegene, Noto Susanto Gultom, and Ho Won Jang. "g -C3N4–Co3O4 Z-Scheme Junction with Green-Synthesized ZnO Photocatalyst for Efficient Degradation of Methylene Blue in Aqueous Solution." Bioinorganic Chemistry and Applications 2023 (June 5, 2023): 1–14. http://dx.doi.org/10.1155/2023/2948342.

Full text

Abstract:

A simple wet chemical ultrasonic-assisted synthesis method was employed to prepare visible light-driven g-C3N4-ZnO-Co3O4 (GZC) heterojunction photocatalysts. X-ray diffraction (XRD), scanning electromicroscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), ultraviolet (UV), and electrochemical impedance spectroscopy (EIS) are used to characterize the prepared catalysts. XRD confirms the homogenous phase formation of g-C3N4, ZnO, and Co3O4, and the heterogeneous phase for the composites. The synthesized ZnO and Co3O4 by using cellulose as a template show a rod-like morphology. The specific surface area of the catalytic samples increases due to the cellulose template. The measurements of the energy band gap of a g-C3N4-ZnO-Co3O4 composite showed red-shifted optical absorption to the visible range. The photoluminescence (PL) intensity decreases due to the formation of heterojunction. The PL quenching and EIS result shows that the reduction of the recombination rate and interfacial resistance result in charge carrier kinetic improvement in the catalyst. The photocatalytic performance in the degradation of MB dye of the GZC-3 composite was about 8.2-, 3.3-, and 2.5-fold more than that of the g-C3N4, g-C3N4-ZnO, and g-C3N4-Co3O4 samples. The Mott–Schottky plots of the flat band edge position of g-C3N4, ZnO, Co3O4, and Z-scheme g-C3N4-ZnO-Co3O4 photocatalysts may be created. Based on the stability experiment, GZC-3 shows greater photocatalytic activity after four recycling cycles. As a result, the GZC composite is environmentally friendly and efficient photocatalyst and has the potential to consider in the treatment of dye-contaminated wastewater.

APA, Harvard, Vancouver, ISO, and other styles

18

Henríquez, Rodrigo, Paula Salazar Nogales, Paula Grez Moreno, Eduardo Muñoz Cartagena, Patricio Leyton Bongiorno, Elena Navarrete-Astorga, and Enrique A. Dalchiele. "One-Step Hydrothermal Synthesis of Cu2ZnSnS4 Nanoparticles as an Efficient Visible Light Photocatalyst for the Degradation of Congo Red Azo Dye." Nanomaterials 13, no. 11 (May 25, 2023): 1731. http://dx.doi.org/10.3390/nano13111731.

Full text

Abstract:

A hydrothermal method was successfully employed to synthesize kesterite Cu2ZnSnS4 (CZTS) nanoparticles. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and optical ultraviolet-visible (UV-vis) spectroscopy were used for characterization of structural, chemical, morphological, and optical properties. XRD results confirmed that a nanocrystalline CZTS phase corresponding to the kesterite structure was formed. Raman analysis confirmed the existence of single pure phase CZTS. XPS results revealed the oxidation states as Cu+, Zn2+, Sn4+, and S2−. FESEM and TEM micrograph images revealed the presence of nanoparticles with average sizes between 7 nm to 60 nm. The synthesized CZTS nanoparticles bandgap was found to be 1.5 eV which is optimal for solar photocatalytic degradation applications. The properties as a semiconductor material were evaluated through the Mott–Schottky analysis. The photocatalytic activity of CZTS has been investigated through photodegradation of Congo red azo dye solution under solar simulation light irradiation, proving to be an excellent photo-catalyst for CR where 90.2% degradation could be achieved in just 60 min. Furthermore, the prepared CZTS was reusable and can be repeatedly used to remove Congo red dye from aqueous solutions.

APA, Harvard, Vancouver, ISO, and other styles

19

Gahlawat, Soniya, Nusrat Rashid, and Pravin P. Ingole. "n-Type Cu2O/α-Fe2O3 Heterojunctions by Electrochemical Deposition: Tuning of Cu2O Thickness for Maximum Photoelectrochemical Performance." Zeitschrift für Physikalische Chemie 232, no. 9-11 (August 28, 2018): 1551–66. http://dx.doi.org/10.1515/zpch-2018-1140.

Full text

Abstract:

Abstract Here, we report the enhanced photoelectrochemical performance of surface modified hematite thin films with n-type copper oxide nanostructures (Cu2O/Fe2O3) obtained through simple electrochemical deposition method. The thickness and amount of cuprous oxide layer were varied by simply changing the number of electrodeposition cycles (viz. 5, 10, 25, 50 and 100) in order to understand its thermodynamic and kinetic influence on the photoelectrochemical activity of the resultant nano-heterostructures. Structural and morphological characteristics of the obtained Cu2O/Fe2O3 films have been studied by absorption spectroscopy, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Electrochemical investigations such as linear sweep voltammetry, Mott–Schottky analysis, and electrochemical impedance spectroscopy suggested the formation of n-type Cu2O layers over the hematite films with varying charge-carrier densities, ranging from 0.56×1019 to 3.94×1019 cm−3, that varies with the number of cycles of electrochemical deposition. Besides, the thickness of deposited cuprous oxide layer is noted to alter the net electrochemical and photo-electrochemical response of the base material. An interesting, peak event was recorded for a particular thickness of the cuprous oxide layer (obtained after 25 cycles of electrochemical deposition) below and above which the efficiency of catalyst was impaired. The heterojunction obtained thus, followed well known Z-scheme and gave appreciable increment in the photocurrent response.

APA, Harvard, Vancouver, ISO, and other styles

20

Zainab K. Ali and Mazin A. Mahdi. "Preparation of Silicon Nanowires Photocathode for Photoelectrochemical Water Splitting." Iraqi Journal of Physics 20, no. 4 (December 1, 2022): 66–81. http://dx.doi.org/10.30723/ijp.v20i4.1070.

Full text

Abstract:

A metal-assisted chemical etching process employing p-type silicon wafers with varied etching durations is used to produce silicon nanowires. Silver nanoparticles prepared by chemical deposition are utilized as a catalyst in the formation of silicon nanowires. Images from field emission scanning electron microscopy confirmed that the diameter of SiNWs grows when the etching duration is increased. The photoelectrochemical cell's characteristics were investigated using p-type silicon nanowires as working electrodes. Linear sweep voltammetry (J-V) measurements on p-SiNWs confirmed that photocurrent density rose from 0.20 mA cm-2 to 0.92 mA cm-2 as the etching duration of prepared SiNWs increased from 15 to 30 min. The conversion efficiency (ƞ) was 0.47 for p-SiNWs prepared with a 15-minute etching time and 0.75 for p-SiNWs prepared with a 30-minute etching time. The cyclic voltammetry (CV) experiments performed at various scan rates validated the faradic behavior of p-SiNWS prepared for 15 and 30 min of etching. Because of the slow ion diffusion and the increased scanning rate, the capacitance decreased with increasing scanning rate. Mott-Schottky (M-S) investigation showed a significant carriers concentration of 3.66×1020 cm-3. According to the results of electrochemical impedance spectroscopy (EIS), the SiNWs photocathode prepared by etching for 30 min had a charge transfer resistance of 25.27 Ω, which is low enough to enhance interfacial charge transfer.

APA, Harvard, Vancouver, ISO, and other styles

21

Wu, Peiwen, Zili Wu, David R. Mullins, Shi-Ze Yang, Xue Han, Yafen Zhang, Guo Shiou Foo, et al. "Promoting Pt catalysis for CO oxidation via the Mott–Schottky effect." Nanoscale 11, no. 40 (2019): 18568–74. http://dx.doi.org/10.1039/c9nr04055b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Kgoetlana, Charlie M., Soraya P. Malinga, and Langelihle N. Dlamini. "Photocatalytic Degradation of Chlorpyrifos with Mn-WO3/SnS2 Heterostructure." Catalysts 10, no. 6 (June 21, 2020): 699. http://dx.doi.org/10.3390/catal10060699.

Full text

Abstract:

Tungsten trioxide (WO3) is a photocatalyst that has gained interest amongst researchers because of its non-toxicity, narrow band gap and superior charge transport. Due to its fast charge recombination, modification is vital to counteract this limitation. In this paper, we report on the fabrication of Mn-doped WO3/SnS2 nanoparticles, which were synthesised with the aim of minimising the recombination rates of the photogenerated species. The nanomaterials were characterised using spectroscopic techniques (UV-Vis-diffuse reflectance spectroscopy (DRS), Raman, XRD, photoluminescence (PL) and electrochemical impedance spectroscopy (EIS)) together with microscopic techniques (FESEM-EDS and high resolution transmission electron microscopy selected area electron diffraction (HRTEM-SAED)) to confirm the successful formation of Mn-WO3/SnS2 nanoparticles. The Mn-doped WO3/SnS2 composite was a mixture of monoclinic and hexagonal phases, confirmed by XRD and Raman analysis. The Mn-WO3/SnS2 heterojunction showed enhanced optical properties compared to those of the un-doped WO3/SnS2 nanoparticles, which confirms the successful charge separation. The Brunauer–Emmett–Teller (BET) analysis indicated that the nanoparticles were mesoporous as they exhibited a Type IV isotherm. These nanomaterials appeared as a mixture of rectangular rods and sheet-like shapes with an increased surface area (77.14 m2/g) and pore volume (0.0641 cm3/g). The electrochemical measurements indicated a high current density (0.030 mA/cm2) and low charge transfer resistance (157.16 Ω) of the Mn-WO3/SnS2 heterojunction, which infers a high charge separation, also complemented by photoluminescence with low emission peak intensity. The Mott–Schottky (M-S) plot indicated a positive slope characteristic of an n–n heterojunction semiconductor, indicating that electrons are the major charge carriers. Thus, the efficiency of Mn-WO3/SnS2 heterojunction photocatalyst was monitored for the degradation of chlorpyrifos. The effects of pH (3–9), catalyst loading (0.1–2 g) and initial chlorpyrifos concentration (100 ppb–20 ppm) were studied. It was observed that the degradation was purely due to photocatalysis, as no loss of chlorpyrifos was observed within 30 min in the dark. Chlorpyrifos removal using Mn-WO3/SnS2 was performed at the optimum conditions of pH = 7, catalyst loading = 1 g and chlorpyrifos concentration = 1000 ppb in 90 min. The complete degradation of chlorpyrifos and its major degradation by-product 3,5,6-trichloropyridin-2-ol (TCP) was achieved. Kinetic studies deduced a second order reaction at 209 × 10−3 M−1s−1.

APA, Harvard, Vancouver, ISO, and other styles

23

Won, Dong-Il, Jong-Su Lee, Ha-Yeon Cheong, Minji Cho, Won-Jo Jung, Ho-Jin Son, Chyongjin Pac, and Sang Ook Kang. "Organic–inorganic hybrid photocatalyst for carbon dioxide reduction." Faraday Discussions 198 (2017): 337–51. http://dx.doi.org/10.1039/c6fd00222f.

Full text

Abstract:

Efficient hybrid photocatalysts for carbon dioxide reduction were developed from dye-sensitized TiO₂ nanoparticles and their catalytic performance was optimized by ternary organic/inorganic components. Thus, the hybrid system consists of (E)-2-cyano-3-(5′-(5′′-(p-(diphenylamino)phenyl)thiophen-2′′-yl)thiophen-2′-yl)-acrylic acid as a sensitizer and fac-[Re(4,4′-bis(diethoxyphosphorylmethyl)-2,2′-bipyridine)(CO)₃Cl] as a reduction catalyst (ReP), both of which have been fixed onto TiO₂ semiconductors (s-TiO₂, h-TiO₂, d-TiO₂). Mott–Schottky analysis on flat-band potential (E_fb) of TiO₂ mesoporous films has verified that E_fb can be finely modulated by volume variation of water (0 to 20 vol%). The increase of added water resulted in substantial positive shifts of E_fb from −1.93 V at 0 vol% H₂O, to −1.74 V (3 vol% H₂O), to −1.56 V (10 vol% H₂O), and to −1.47 V (20 vol% H₂O). As a result, with addition of 3–10 vol% water in the photocatalytic reaction, conversion efficiency of CO₂ to CO increased significantly reaching a TON value of ∼350 for 30 h. Catalytic activity enhancement is mainly attributed to (1) the optimum alignment of E_fb by 3–10 vol% water with respect to the of the dye and E_red of ReP for smooth electron transfer from photo-excited dye to RePvia the TiO₂ semiconductor and (2) the water-induced acceleration of chemical processes on the fixed ReP. In addition, the energy level was further tuned by variation of the dye and ReP amounts. We also found that the intrinsic properties of TiO₂ sources (morphology, size, agglomeration) exert a great influence on the overall photocatalytic activity of this hybrid system. Implications of the present observations and reaction mechanisms are discussed in detail.

APA, Harvard, Vancouver, ISO, and other styles

24

Zhang, Guangqiang, Hong Su, and Yan Zhang. "Construction of Glutinous Rice Potpourri-like MOTT−Schottky Ni/CeO2 Heterojunction Nanosheets for Robust Electrochemical Water Reduction." Energies 15, no. 24 (December 13, 2022): 9443. http://dx.doi.org/10.3390/en15249443.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

25

Lee, Siaw Foon, Eva Jimenez-Relinque, Isabel Martinez, and Marta Castellote. "Effects of Mott–Schottky Frequency Selection and Other Controlling Factors on Flat-Band Potential and Band-Edge Position Determination of TiO2." Catalysts 13, no. 6 (June 13, 2023): 1000. http://dx.doi.org/10.3390/catal13061000.

Full text

Abstract:

The use of titanium dioxide for tackling environmental pollution has attracted great research interest recently. The potential of a photocatalyst in removing contaminants depends mainly on its conduction and valence-band edges relative to the standard potential of reactive oxygen species. One of the methods used in determining these band-edge positions is via the Mott–Schottky analysis. Thus, the aim of this work was to investigate the influence of the Mott–Schottky frequency and different electrochemical conditions on flat-band potential values and band-edge positions of pure anatase or Degussa P25, calcined or uncalcined in a 0.2 M Na2SO4 solution. The results showed that the shift in the flat-band potential was not so frequency-dependent in the Mott–Schottky analysis, however, other reasons, such as immersion duration leading to thenardite Na2SO4 salt deposition on the surface, irradiation of sources and the change in the pH of the solution (in the range of 1.64–12.11) were also responsible for it. In general, both the calcined anatase and P25 had a less negative value of the flat-band potential compared to the uncalcined. On the other hand, the calcined anatase had a tendency to have a less negative value of the flat-band potential than the calcined P25. From this study, the frequency range for obtaining the flat-band potential within one standard deviation in the Mott–Schottky at a single-frequency analysis was found to be between 200 and 2000 Hz. The energy difference between the Fermi level and the conduction band edge for anatase and P25, either calcined or uncalcined, was 0.097–0.186 and 0.084–0.192 eV, respectively. On the other hand, the band-edge position of anatase or P25 tended to shift upwards when it was repeatedly used in the photoelectrochemical analysis.

APA, Harvard, Vancouver, ISO, and other styles

26

Matsuzawa, Koichi, Atsushi Nozaka, and Akimitsu Ishihara. "(Digital Presentation) Mo Added Zr Oxide-Based Thin Film for Oxygen Evolution Catalyst in Alkaline Solution." ECS Meeting Abstracts MA2022-01, no. 34 (July 7, 2022): 1347. http://dx.doi.org/10.1149/ma2022-01341347mtgabs.

Full text

Abstract:

On Oct. 4, 2021, Hydrogen energy ministerial meeting (H2 EM 2021) was held by the ministry of economy, trade and industry (METI) of Japanese government as online special event with cabinet members and officials from 29 countries, regions, and organizations. In the meeting, “Global Hydrogen Review 2021” and was released to propose the policy toward hydrogen-based society. In the open session, the water electrolysis was one of the main session, and participants shared their commitment to improve the performance of water electrolysis units and optimize the relevant systems with a view toward reducing the costs of “Green Hydrogen”, and exchanged views on topics including the future prospects for the “Green Hydrogen” market [1]. Here, “Green Hydrogen” is the hydrogen which is produced by the electricity from renewable energies introducing in our previous study [2]. Alkaline water electrolysis (AWE) has already commercialized all over the world and recently applied its system for the Power-to-Gas (PtG) in Europe and Japan such as Fukushima hydrogen energy research field (FH2R). In the FH2R, one of the largest module of AWE has operated from 2020. However, we found that the degradation of Ni anode occurs operating by variable renewable energy (VNE) from our previous report [3]. From this point of view, the alternative anode with high durability against VNE should be required for green hydrogen production. We focused on zirconium oxide-based electrocatalyst (ZrOx) and have studied its catalytic activity for oxygen evolution reaction (OER) [4]. In this study, we have investigated the activity and durability of ZrOx with and without Mo addition for the OER in alkaline solution. Zr compound films were formed on Ti rods as a base material, using the R.F. magnetron sputtering. Gas atmosphere in the chamber was a mixture of Ar and O2 gas. After polishing and washing, the Ti rods were heated at 300 oC for Zr oxide-based film without any addition (ZrOx), and 350 oC for Zr oxide-based film with Mn addition (Mn-ZrOx). Sputtering power and sputtering time were fixed at 150 W and 20 min, respectively. All electrochemical measurements were carried out using a three-electrode cell at 30 oC in 7 M KOH. A reversible hydrogen electrode (RHE) and a carbon plate were used as a reference and a counter electrode, respectively. ZrOx or Mo-ZrOx was used as working electrode. In order to evaluate the catalytic activity for the OER, slow scan voltammetry (SSV) was performed under N2 atmosphere. Current density (i geo) was based on the geometric surface area of the working electrode. The resistance of the film (R film) and charge transfer (R ct) was evaluated by AC impedance spectroscopic measurements in the frequency range from 105 to 10−1 Hz. Figure 1 shows polarization curves of ZrOx and Mo-ZrOx. The i geo for the OER on Mo-ZrOx has obviously larger than that of ZrOx. According to the cyclic voltammograms (CV) of both sample, the electric double layer (C dl) of Mo-ZrOx from CV was larger than that of ZrOx. This trend was similar to the result reported in previous study [5], and it is suggested that the C dl becomes larger by the effect of Mo addition. From the results of electrochemical impedance spectroscopy (EIS), both ZrOx and Mo-ZrOx are n-type semiconductor. Moreover, the slope of Mott-Schottky plot on Mo-ZrOx was more gentle than that on ZrOx and it is suggested that the electric conductivity of Mo-ZrOx was larger than that of ZrOx. Thus, the reason why the i geo for the OER on Mo-ZrOx has larger than that of ZrOx is that both improvement of the increase of C dl and the electric conductivity of sample. Acknowledgement: This work is partially supported by Iketani Science and Technology Foundation. Reference [1] https://www.meti.go.jp/english/press/2021/1008_001.html [2] K. Ota, A. Ishihara, K. Matsuzawa, and S. Mitsushima, Electrochemistry, 78, 970 (2010). [3] H. Ichikawa, K. Matsuzawa, Y. Kohno, I. Nagashima, Y. Sunada, Y. Nishiki, A. Manabe, and S. Mitsushima, ECS Trans., 58(33), 9 (2014). [4] K. Matsuzawa, A. Ishihara, A. Ohshi, S. Mitsushima, and K. Ota, Mater. Sci. Eng. B, 267, 115112 (2020). [5] Y. Takasu, T. Ohnuma, W. Sugimoto, and Y. Murakami, Electrochemistry, 67, 1187 (1999). Figure 1

APA, Harvard, Vancouver, ISO, and other styles

27

Wang, Lu, Yue Zhao, Linghao Liu, Ziyi Zheng, Zijun Liu, Fuhao Zhang, Lin Wang, and Zhuangjun Fan. "Acetylene functionalized covalent triazine frameworks with AuPd nanoparticles as photocatalysts for hydrogen evolution from formic acid." IOP Conference Series: Earth and Environmental Science 1171, no. 1 (April 1, 2023): 012024. http://dx.doi.org/10.1088/1755-1315/1171/1/012024.

Full text

Abstract:

Abstract Photocatalytic dehydrogenation of formic acid (FA) at room temperature is a promising way to meet the increasing demand for hydrogen energy. In this work, we loaded nanoparticles of plasmonic AuPd alloys on the acetylene functionalized covalent triazine frameworks (CTFs) for the design of Mott-Schottky catalysts (AuPd/CTFs) with further application to photocatalytic hydrogen production from FA. Experimental data showed that the introduction of acetylene (-C≡C-) unit and AuPd alloy into the CTF could significantly enhance the performance of hydrogen evolution. The results of photoelectrochemical tests showed that the introduction of carbon-carbon triple bonds and AuPd alloy could adjust the electronic structure of CTF and inhibit charge recombination. Thus, benefiting from these positive effects, the FA photocatalytic decomposition by the obtained AuPd-CTF-EDDBN photocatalyst yielded H2 at a good rate of 10600 μmol·gcat −1·h−1.

APA, Harvard, Vancouver, ISO, and other styles

28

Mureseanu, Mihaela, Nicoleta Cioatera, and Gabriela Carja. "Fe-Ce/Layered Double Hydroxide Heterostructures and Their Derived Oxides: Electrochemical Characterization and Light-Driven Catalysis for the Degradation of Phenol from Water." Nanomaterials 13, no. 6 (March 8, 2023): 981. http://dx.doi.org/10.3390/nano13060981.

Full text

Abstract:

Fe-Ce/layered double hydroxides (LDHs) were synthesized via a facile route by exploiting the “structural memory” of the LDH when the calcined MgAlLDH and ZnAlLDH were reconstructed in the aqueous solutions of FeSO4/Ce(SO4)2. XRD analysis shows the formation of heterostructured catalysts that entangle the structural characteristics of the LDHs with those of Fe2O3 and CeO2. Furthermore, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, TG/DTG, SEM/EDX and TEM results reveal a complex morphology defined by the large nano/microplates of the reconstructed LDHs that are tightly covered with nanoparticles of Fe2O3 and CeO2. Calcination at 850 °C promoted the formation of highly crystallized mixed oxides of Fe2O3/CeO2/ZnO and spinels. The photo-electrochemical behavior of Fe-Ce/LDHs and their derived oxides was studied in a three-electrode photo-electrochemical cell, using linear sweep voltammetry (LSV), Mott–Schottky (M-S) analysis and photo-electrochemical impedance spectroscopy (PEIS) measurements, in dark or under illumination. When tested as novel catalysts for the degradation of phenol from aqueous solutions, the light-driven catalytic heterojunctions of Fe-Ce/LDH and their derived oxides reveal their capabilities to efficiently remove phenol from water, under both UV and solar irradiation.

APA, Harvard, Vancouver, ISO, and other styles

29

Permporn, Darika, Rattabal Khunphonoi, Jetsadakorn Wilamat, Pongtanawat Khemthong, Prae Chirawatkul, Teera Butburee, Weradesh Sangkhun, et al. "Insight into the Roles of Metal Loading on CO2 Photocatalytic Reduction Behaviors of TiO2." Nanomaterials 12, no. 3 (January 29, 2022): 474. http://dx.doi.org/10.3390/nano12030474.

Full text

Abstract:

The photocatalytic reduction of carbon dioxide (CO2) into value-added chemicals is considered to be a green and sustainable technology, and has recently gained considerable research interest. In this work, titanium dioxide (TiO2) supported Pt, Pd, Ni, and Cu catalysts were synthesized by photodeposition. The formation of various metal species on an anatase TiO2 surface, after ultraviolet (UV) light irradiation, was investigated insightfully by the X-ray absorption near edge structure (XANES) technique. CO2 reduction under UV-light irradiation at an ambient pressure was demonstrated. To gain an insight into the charge recombination rate during reduction, the catalysts were carefully investigated by the intensity modulated photocurrent spectroscopy (IMPS) and photoluminescence spectroscopy (PL). The catalytic behaviors of the catalysts were investigated by density functional theory using the self-consistent Hubbard U-correction (DFT+U) approach. In addition, Mott–Schottky measurement was employed to study the effect of energy band alignment of metal-semiconductor on CO2 photoreduction. Heterojunction formed at Pt-, Pd-, Ni-, and Cu-TiO2 interface has crucial roles on the charge recombination and the catalytic behaviors. Furthermore, it was found that Pt-TiO2 provides the highest methanol yield of 17.85 µmol/gcat/h, and CO as a minor product. According to the IMPS data, Pt-TiO2 has the best charge transfer ability, with the mean electron transit time of 4.513 µs. We believe that this extensive study on the junction between TiO2 could provide a profound understanding of catalytic behaviors, which will pave the way for rational designs of novel catalysts with improved photocatalytic performance for CO2 reduction.

APA, Harvard, Vancouver, ISO, and other styles

30

Xu, Zhixiao, Song Jin, Min Ho Seo, and Xiaolei Wang. "Hierarchical Ni-Mo2C/N-doped carbon Mott-Schottky array for water electrolysis." Applied Catalysis B: Environmental 292 (September 2021): 120168. http://dx.doi.org/10.1016/j.apcatb.2021.120168.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Cai, Yi-Yu, Xin-Hao Li, Ya-Nan Zhang, Xiao Wei, Kai-Xue Wang, and Jie-Sheng Chen. "Highly Efficient Dehydrogenation of Formic Acid over a Palladium-Nanoparticle-Based Mott-Schottky Photocatalyst." Angewandte Chemie International Edition 52, no. 45 (September 23, 2013): 11822–25. http://dx.doi.org/10.1002/anie.201304652.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Peng, Lingxin, Liang Su, Xu Yu, Rongyan Wang, Xiangzhi Cui, Han Tian, Shaowen Cao, Bao Yu Xia, and Jianlin Shi. "Electron redistribution of ruthenium-tungsten oxides Mott-Schottky heterojunction for enhanced hydrogen evolution." Applied Catalysis B: Environmental 308 (July 2022): 121229. http://dx.doi.org/10.1016/j.apcatb.2022.121229.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Kang, Yao, Shuo Wang, Kwan San Hui, Shuxing Wu, Duc Anh Dinh, Xi Fan, Feng Bin, et al. "Surface reconstruction establishing Mott-Schottky heterojunction and built-in space-charging effect accelerating oxygen evolution reaction." Nano Research 15, no. 4 (December 12, 2021): 2952–60. http://dx.doi.org/10.1007/s12274-021-3917-7.

Full text

Abstract:

AbstractStructural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities. However, how to properly facilitate surface reconstruction to overcome large overpotential that stimulate the surface reconstruction has remained elusive. Herein, we adopt a facile approach to activate surface reconstruction on Ni(OH)2 by incorporating F anions to achieve electro-derived structural oxidation process and further boost its oxygen evolution reaction (OER) activity. Ex situ Raman and X-ray photoemission spectroscopy studies indicate that F ions incorporation facilitated surface reconstruction and promotes the original Ni(OH)2 transformed into a mesoporous and amorphous F-NiOOH layer during the electrochemical process. Density functional theory (DFT) calculation reveals that this self-reconstructed NiOOH induces a space-charge effect on the p-n junction interface, which not only promotes the absorption of intermediates species (*OH, *O, and *OOH) and charge-transfer process during catalysis, but also leads to a strong interaction of the p-n junction interface to stabilize the materials. This work opens up a new possibility to regulate the electronic structure of active sites and promote their catalytic activities.

APA, Harvard, Vancouver, ISO, and other styles

34

Yuan, Menglei, Junwu Chen, Yiling Bai, Zhanjun Liu, Jingxian Zhang, Tongkun Zhao, Qin Wang, Shuwei Li, Hongyan He, and Guangjin Zhang. "Unveiling Electrochemical Urea Synthesis by Co‐Activation of CO 2 and N 2 with Mott–Schottky Heterostructure Catalysts." Angewandte Chemie 133, no. 19 (April 8, 2021): 11005–13. http://dx.doi.org/10.1002/ange.202101275.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Yuan, Menglei, Junwu Chen, Yiling Bai, Zhanjun Liu, Jingxian Zhang, Tongkun Zhao, Qin Wang, Shuwei Li, Hongyan He, and Guangjin Zhang. "Unveiling Electrochemical Urea Synthesis by Co‐Activation of CO 2 and N 2 with Mott–Schottky Heterostructure Catalysts." Angewandte Chemie International Edition 60, no. 19 (April 8, 2021): 10910–18. http://dx.doi.org/10.1002/anie.202101275.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Zhang, Zhicheng, Wei Cai, Shaopeng Rong, Hongxia Qu, and Huifang Xie. "Hollow CuFe2O4/MgFe2O4 Heterojunction Boost Photocatalytic Oxidation Activity for Organic Pollutants." Catalysts 12, no. 8 (August 18, 2022): 910. http://dx.doi.org/10.3390/catal12080910.

Full text

Abstract:

P-n heterojunction-structured CuFe2O4/MgFe2O4 hollow spheres with a diameter of 250 nm were synthesized using a template-free solvothermal method, and time-dependent morphological studies were carried out to investigate the hollow formation mechanism. The CuFe2O4/MgFe2O4 with a molar ratio of 1:2 (Cu:Mg) had the highest degradation efficiency with the model organic dye Acid Orange 7, with a degradation rate of 91.96% over 60 min. The synthesized CuFe2O4/MgFe2O4 nanocomposites were characterized by XRD, TEM, HRTEM, UV-vis spectroscopy, Mott–Schottky, and EIS. Due to the synthesis of the p-n heterojunction, CuFe2O4/MgFe2O4 has efficient photogenerated carriers, and the hollow structure has a higher specific surface area and stronger adsorption capacity, which is significantly better than that of CuFe2O4 and MgFe2O4 in terms of photocatalytic performance. The outstanding performance shows that the p-n heterostructure of CuFe2O4/MgFe2O4 has potential for application in wastewater degradation.

APA, Harvard, Vancouver, ISO, and other styles

37

Li, Zhen, Zhuoyang Gao, Bingwen Li, Lili Zhang, Rong Fu, Yan Li, Xiaoyue Mu, and Lu Li. "Fe-Pt nanoclusters modified Mott-Schottky photocatalysts for enhanced ammonia synthesis at ambient conditions." Applied Catalysis B: Environmental 262 (March 2020): 118276. http://dx.doi.org/10.1016/j.apcatb.2019.118276.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Shang, Wenxue, Yi Xiao, Airu Yu, Hongxia Shen, Qiong Cheng, Yantao Sun, Liqiu Zhang, Lichun Liu, and Lihua Li. "Visible-Light-Enhanced Electrocatalytic Hydrogen Evolution Using Electrodeposited Molybdenum Oxide." Journal of The Electrochemical Society 169, no. 3 (March 1, 2022): 034529. http://dx.doi.org/10.1149/1945-7111/ac5d94.

Full text

Abstract:

Electrocatalytic hydrogen production using inexpensive catalysts and solar energy has become a critical research direction due to its economic interest and environmental friendliness. Photoresponsive semiconductors play a key role in this field. In this work, we demonstrate visible light-responsive, mixed-valence, molybdenum oxide (MoO3−x, 0 ≤ x ≤ 1) thin films with oxygen vacancies that are electrochemically deposited in a period of seconds through an ammonium heptamolybdate electrolyte. XRD, XPS, SEM, TEM, EPR, Raman, and electrochemical techniques (Linear Sweep Voltammetry, Chronoamperometry, Electrochemical Impedance Spectroscopy, Tafel analysis) have been utilized to characterize the MoO3−x films. Diffuse reflectance spectroscopy (DRS) and the Mott-Schottky (MS) plot reveal that the as-deposited semiconductive MoO3−x film possesses an optical bandgap of ∼2.53 eV and a flat band potential of ∼0.40 eV, respectively. The MoO3−x films exhibit up to 152% electrocatalytic current improvement in the hydrogen evolution reaction (HER) upon illumination with visible light compared to in the dark. The superior electrocatalytic activity of the as-deposited MoO3−x films under illumination is attributed to the lower bandgap, lower overpotential, decreased electronic resistivity, and a smaller Tafel slope. Our experimental exploration suggests that MoO3−x can be potentially applied as an effective, low-cost electrode material for high-performance solar energy-assisted hydrogen fuel production.

APA, Harvard, Vancouver, ISO, and other styles

39

Zhang, Shengbo, Mei Li, Jiankang Zhao, Hua Wang, Xinli Zhu, Jinyu Han, and Xiao Liu. "Plasmonic AuPd-based Mott-Schottky photocatalyst for synergistically enhanced hydrogen evolution from formic acid and aldehyde." Applied Catalysis B: Environmental 252 (September 2019): 24–32. http://dx.doi.org/10.1016/j.apcatb.2019.04.013.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Dong, Qing, Gangjian Li, Fangfang Liu, Jianwei Ren, Hui Wang, and Rongfang Wang. "Cu nanoclusters activating ultrafine Fe3N nanoparticles via the Mott-Schottky effect for rechargeable zinc-air batteries." Applied Catalysis B: Environmental 326 (June 2023): 122415. http://dx.doi.org/10.1016/j.apcatb.2023.122415.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Ismael, Mohammed, and Michael Wark. "Perovskite-type LaFeO3: Photoelectrochemical Properties and Photocatalytic Degradation of Organic Pollutants Under Visible Light Irradiation." Catalysts 9, no. 4 (April 8, 2019): 342. http://dx.doi.org/10.3390/catal9040342.

Full text

Abstract:

Perovskite-type oxides lanthanum ferrite (LaFeO3) photocatalysts were successfully prepared by a facile and cost-effective sol-gel method using La(NO)3 and Fe(NO)3 as metal ion precursors and citric acid as a complexing agent at different calcination temperatures. The properties of the resulting LaFeO3 samples were characterized by powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS), UV-Vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (IR), transmission electron microscopy (TEM), N2 adsorption/desorption and photoelectrochemical tests. The photoactivity of the LaFeO3 samples was tested by monitoring the photocatalytic degradation of Rhodamine B (RhB) and 4-chlorophenol (4-CP) under visible light irradiation, the highest photocatalytic activity was found for LaFeO3 calcined at 700 °C, which attributed to the relatively highest surface area (10.6 m2/g). In addition, it was found from trapping experiments that the reactive species for degradation were superoxide radical ions (O2−) and holes (h+). Photocurrent measurements and electrochemical impedance spectroscopy (EIS) proved the higher photo-induced charge carrier transfer and separation efficiency of the LaFeO3 sample calcined at 700 °C compared to that that calcined at 900 °C. Band positions of LaFeO3 were estimated using the Mott-Schottky plots, which showed that H2 evolution was not likely.

APA, Harvard, Vancouver, ISO, and other styles

42

Thanh Thuy, Chau Thi, Gyuho Shin, Lee Jieun, Hyung Do Kim, Ganesh Koyyada, and Jae Hong Kim. "Self-Doped Carbon Dots Decorated TiO2 Nanorods: A Novel Synthesis Route for Enhanced Photoelectrochemical Water Splitting." Catalysts 12, no. 10 (October 20, 2022): 1281. http://dx.doi.org/10.3390/catal12101281.

Full text

Abstract:

Herein, we have successfully prepared self-doped carbon dots with nitrogen elements (NCD) in a simple one-pot hydrothermal carbonization method, using L-histidine as a new precursor. The effect of as-prepared carbon dots was studied for photoelectrochemical (PEC) water splitting by decorating NCDs upon TiO2 nanorods systematically by changing the loading time from 2 h to 8 h (TiO2@NCD2h, TiO2@NCD4h, TiO2@NCD6h, and TiO2@NCD8h). The successful decorating of NCDs on TiO2 was confirmed by FE-TEM and Raman spectroscopy. The TiO2@NCD4h has shown a photocurrent density of 2.51 mA.cm−2, 3.4 times higher than the pristine TiO2. Moreover, TiO2@NCD4h exhibited 12% higher applied bias photon-to-current efficiency (ABPE) than the pristine TiO2. The detailed IPCE, Mott–Schottky, and impedance (EIS) analyses have revealed the enhanced light harvesting property, free carrier concentration, charge separation, and transportation upon introduction of the NCDs on TiO2. The obtained results clearly portray the key role of NCDs in improving the PEC performance, providing a new insight into the development of highly competent TiO2 and NCDs based photoanodes for PEC water splitting.

APA, Harvard, Vancouver, ISO, and other styles

43

Wei, Qinhong, Jiashi Wang, and Wenzhong Shen. "Atomically dispersed Feδ+ anchored on nitrogen-rich carbon for enhancing benzyl alcohol oxidation through Mott-Schottky effect." Applied Catalysis B: Environmental 292 (September 2021): 120195. http://dx.doi.org/10.1016/j.apcatb.2021.120195.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Zhang, Pengfei, Yaoda Liu, Tingting Liang, Edison Huixiang Ang, Xu Zhang, Fei Ma, and Zhengfei Dai. "Nitrogen-doped carbon wrapped Co-Mo2C dual Mott–Schottky nanosheets with large porosity for efficient water electrolysis." Applied Catalysis B: Environmental 284 (May 2021): 119738. http://dx.doi.org/10.1016/j.apcatb.2020.119738.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

He, Tianwei, Gurpreet Kour, Xin Mao, and Aijun Du. "Cuδ+ active sites stabilization through Mott-Schottky effect for promoting highly efficient conversion of carbon monoxide into n-propanol." Journal of Catalysis 382 (February 2020): 49–56. http://dx.doi.org/10.1016/j.jcat.2019.12.015.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Li, Zhen, Ligong Zhai, Tingting Ma, Jinfeng Zhang, and Zhenghua Wang. "Efficient and Stable Catalytic Hydrogen Evolution of ZrO2/CdSe-DETA Nanocomposites under Visible Light." Catalysts 12, no. 11 (November 8, 2022): 1385. http://dx.doi.org/10.3390/catal12111385.

Full text

Abstract:

Composite photocatalysts are crucial for photocatalytic hydrogen evolution. In this work, ZrO2/CdSe-diethylenetriamine (ZrO2/CdSe-DETA) heterojunction nanocomposites are synthesized, and efficiently and stably catalyzed hydrogen evolution under visible light. X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscope (HRTEM) confirm the formation of heterojunctions between ZrO2 (ZO) and CdSe-DETA (CS). Ultraviolet–visible spectroscopy diffuse reflectance spectra (UV-vis DRS), Mott–Schottky, and theoretical calculations confirm that the mechanism at the heterojunction of the ZrO2/CdSe-DETA (ZO/CS) nanocomposites is Type-I. Among the ZO/CS nanocomposites (ZO/CS-0.4, ZO/CS-0.6, and ZO/CS-0.8; in the nanocomposites, the mass ratio of ZO to CS is 0.1:0.0765, 0.1:0.1148, and 0.1:0.1531, respectively). ZO/CS-0.6 nanocomposite has the best photocatalytic hydrogen evolution activity (4.27 mmol g−1 h−1), which is significantly higher than ZO (trace) and CS (1.75 mmol g−1 h−1). Within four cycles, the ZO/CS-0.6 nanocomposite maintains an efficient catalytic hydrogen evolution rate. Due to the existence of the heterojunction of the composites, the photogenerated electron-hole pairs can be effectively separated, which accelerates the photocatalytic hydrogen evolution reaction and reduces the progress of photocorrosion. This work reveals the feasibility of ZO/CS nanocomposite photocatalysts for hydrogen evolution.

APA, Harvard, Vancouver, ISO, and other styles

47

Liu, Bo, Tong Xu, Chunping Li, and Jie Bai. "Activating Pd nanoparticles via the Mott-Schottky effect in Ni doped CeO2 nanotubes for enhanced catalytic Suzuki reaction." Molecular Catalysis 528 (August 2022): 112452. http://dx.doi.org/10.1016/j.mcat.2022.112452.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Nkwachukwu, Oluchi V., Charles Muzenda, Babatope O. Ojo, Busisiwe N. Zwane, Babatunde A. Koiki, Benjamin O. Orimolade, Duduzile Nkosi, Nonhlangabezo Mabuba, and Omotayo A. Arotiba. "Photoelectrochemical Degradation of Organic Pollutants on a La3+ Doped BiFeO3 Perovskite." Catalysts 11, no. 9 (September 2, 2021): 1069. http://dx.doi.org/10.3390/catal11091069.

Full text

Abstract:

Towards nonconventional wastewater treatment methods for the degradation of organic pollutants in wastewater, a perovskite-based photoelectrochemical system was developed. Bismuth ferrite doped with lanthanum (La-BiFeO3, La-BFO) perovskite was synthesised through a hydrothermal method with low calcination temperature for the photoelectrochemical degradation of orange II dye and other cocktails of dyes. Photoanodes were prepared by the deposition of the perovskites on a fluorine-doped tin oxide (FTO) substrate. The photoanodes were characterised using XRD, FESEM, FTIR and UV-vis diffuse reflectance. The photoelectrochemical properties of the synthesised photoanodes were investigated with chronoamperometry and electrochemical impedance spectroscopy (including Mott–Schottky analysis). The results show that all La3+-doped BFO photoanodes exhibited a higher absorption edge in the visible light region than the undoped BFO. The photocurrent response of 10% La-BFO (the best performing electrode) exhibited a three times higher current response than the pure BFO. In addition, the electrode exhibited a good degradation efficiency of 84.2% within 120 min with applied bias potential of 2 V at a pH of 7. EIS studies showed a significant enhancement of the interfacial electron transfer of the charge carriers. The enhancements in electrode performances were attributed to the synergistic effect of the applied bias potential and the introduction of La3+ into the BFO matrix. This study therefore shows that the photoelectrocatalytic performance of BFO for water treatment can be improved by the introduction of perovskites-doping ions such as La3+.

APA, Harvard, Vancouver, ISO, and other styles

49

Koh, Tae Sik, Periyasamy Anushkkaran, Jun Beom Hwang, Sun Hee Choi, Weon-Sik Chae, Hyun Hwi Lee, and Jum Suk Jang. "Magnetron Sputtered Al Co-Doped with Zr-Fe2O3 Photoanode with Fortuitous Al2O3 Passivation Layer to Lower the Onset Potential for Photoelectrochemical Solar Water Splitting." Catalysts 12, no. 11 (November 18, 2022): 1467. http://dx.doi.org/10.3390/catal12111467.

Full text

Abstract:

In this paper, we investigate the magnetron sputtering deposition of an Al-layer on Zr-doped FeOOH (Zr-FeOOH) samples to fabricate a Zr/Al co-doped Fe2O3 (Al-Zr/HT) photoanode. An Al-layer is deposited onto Zr-FeOOH through magnetron sputtering and the thickness of the Al deposition is regulated by differing the sputtering time. Electrochemical impedance spectroscopy, intensity-modulated photocurrent spectroscopy, Mott-Schottky and time-resolved photoluminescence spectra analyses were used to study, in depth, the correlations between sputtered Al-layer thicknesses and PEC characteristics. High-temperature quenching (800 °C) assists in diffusing the Al3+ in the bulk of the Zr-doped Fe2O3 photoanode, whilst an unintended Al2O3 passivation layer forms on the surface. The optimized Al-Zr/HT photoelectrode achieved 0.945 mA/cm2 at 1.0 VRHE, which is 3-fold higher than that of the bare Zr/HT photoanode. The Al2O3 passivation layer causes a 100 mV cathodic shift in the onset potential. Al co-doping improved the donor density, thus reducing the electron transit time. In addition, the passivation effect of the Al2O3 layer ameliorated the surface charge transfer kinetics. The Al2O3 passivation layer suppressed the surface charge transfer resistance, consequently expediting the hole migration from photoanode to electrolyte. We believe that the thickness-controlled Al-layer sputtering approach could be applicable for various metal oxide photoanodes to lower the onset potential.

APA, Harvard, Vancouver, ISO, and other styles

50

Zhang, Quan, Fang Luo, Xue Long, Xinxin Yu, Konggang Qu, and Zehui Yang. "N, P doped carbon nanotubes confined WN-Ni Mott-Schottky heterogeneous electrocatalyst for water splitting and rechargeable zinc-air batteries." Applied Catalysis B: Environmental 298 (December 2021): 120511. http://dx.doi.org/10.1016/j.apcatb.2021.120511.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Mott-Schottky Catalyst'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles