Nanomaterials
·
2021
·Vol. 11
·期 11
·2940
·
IF 5.076
Bingke Zhang,Shengwen Fu,Dongbo Wang,Shujie Jiao,Zhi Zeng,Xiangyu Zhang,Zhikun Xu,Yaxin Liu,Chenchen Zhao,Jingwen Pan,Donghao Liu,Jinzhong Wang
The photocatalysis technique has been proven to be a promising method to solve environmental pollution in situations of energy shortage, and has been intensively investigated in the field of pollutant degradation. In this work, a band structure-controlled solid solution of BiOBrXI1−X(x = 0.00, 0.05, 0.10, 0.15, 0.20, 1.00) with highly efficient light-driven photocatalytic activities was successfully synthesized via simple solvothermal methods. The phase composition, crystal structure, morphology, internal molecular vibration, optical properties, and energy band structure were characterized and analyzed by XRD, SEM, HRTEM, XPS, Raman, and UV Vis DRS. To evaluate the photocatalytic activity of BiOBrXI1−X, rhodamine B was selected as an organic pollutant. In particular, BiOBr0.15I0.85displayed significantly enhanced photocatalytic activity by virtue of modulating the energy band position, optimizing redox potentials, and accelerating carrier separation. Moreover, the enhancement mechanism was elucidated on the basis of band structure engineering, which provides ideas for the design of highly active photocatalysts for practical application in the fields of environmental issues and energy conservation.Keywords:BiOBrXI1−X;solid solution;photocatalytic degradation;band structure engineering
研究领域:
环境科学
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材料科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
Nature Catalysis
·
2020
·Vol. 3
·期 11
·932-940
·
IF 30.471
Xiao Yequan,Feng Chao,Fu Jie,Wang Faze,Li Changli,Kunzelmann Viktoria F.,Jiang Chang-Ming,Nakabayashi Mamiko,Shibata Naoya,Sharp Ian D.,Domen Kazunari,Li Yanbo
Ta 3 N 5 is a promising photoanode material with a theoretical maximum solar conversion efficiency of 15.9% for photoelectrochemical water splitting. However, the highest applied bias photon-to-current efficiency achieved so far is only 2.72%. To bridge the efficiency gap, effective carrier management strategies for Ta 3 N 5 photoanodes should be developed. Here, we propose to use gradient Mg doping for band structure engineering and defect control of Ta 3 N 5 . The gradient Mg doping profile in Ta 3 N 5 induces a gradient of the band edge energetics, which greatly enhances the charge separation efficiency. Furthermore, defect-related recombination is significantly suppressed due to the passivation effect of Mg dopants on deep-level defects and, more importantly, the matching of the gradient Mg doping profile with the distribution of defects within Ta 3 N 5 . As a result, a photoanode based on the gradient Mg-doped Ta 3 N 5 delivers a low onset potential of 0.4 V versus that of a reversible hydrogen electrode and a high applied bias photon-to-current efficiency of 3.25 ± 0.05%.
研究领域:
材料科学
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光电化学
·
半导体物理
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 38
·2303736
·
IF 19
Qiong Liu,Faqi Zhan,Hang Luo,Xiaogang Luo,Qiuyan Yi,Qiwei Sun,Zhida Xiao,Yan Zhang,Dou Zhang,Chris R. Bowen
The piezoelectric enhancement of photo-catalytic activity for water splitting and pollutant degradation is a novel approach to developing renewable energy and environmental protection applications. Herein, a new form of defect engineered Na-Sm bimetallic-regulated CaBi 2 Nb 2 O 9 platelet is synthesized via a molten salt process for water splitting and pollutant degradation applications. An intermediate band structure is introduced by Sm-doping, and empty orbitals in the conductive band are introduced by Na-doping. These factors, combined with the increased local charge density around the Sm and Na atoms, result in an increased electrical conductivity, improved electron mobility, and provide additional electrons for enhancing catalytic reactions. As a consequence, the judicious co-doping of CaBi 2 Nb 2 O 9 with Sm and Na leads to a unique synergetic piezo-photo-electric effect to provide a superior piezo-photo-catalytic performance for H 2 production (158.53 µmol g −1 h −1 ) and pollutant degradation (rate constant, k = 0.257 min −1 ). This new approach provides important insights into the application of defect engineering to exploit the cooperative doping of alkaline earth metals and rare metals to create high-performance catalysts.
研究领域:
材料科学
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催化
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环境科学
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能源材料
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固体化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Yaqiao Liu,Shuozhen Hu,Zhaoqun Gao,Xinsheng Zhang,Shigang Sun
Photoelectrochemical (PEC) water oxidation is considered to be a promising approach to converting solar energy into clean chemical fuels. α-Fe2O3 is a potential photoanode material for water oxidation with a high theoretical photocurrent density (12.6 mA cm–2) driven by visible light. Constructing α-Fe2O3-based heterojunction with other semiconductors is a promising strategy to improve the actual photoelectrocatalytic activity. In this work, nitrogen-doped Ta2O5 is introduced to synthesize N-Ta2O5-h@α-Fe2O3 nanorod heterojunction with different band structures. At the interface, electrons transfer from N-Ta2O5-h to α-Fe2O3, which forms a built-in electric field. The heterojunction structure contributes to inhibiting the severe recombination of photogenerated electron–hole pairs. By controlling the duration of mild heat treatment, the N-Ta2O5-h nanorods with different Fermi energy levels and contents of oxygen vacancies are obtained. A mild heat treatment in N2 is proved to enlarge the ΔE by leveling up the Fermi level and to promote the content of oxygen vacancies for the N-Ta2O5-h@α-Fe2O3 heterojunction as the heat-treatment time increases. The PEC water oxidation performance of the N-Ta2O5-h@α-Fe2O3 heterojunction increases when the mild-heat-treatment time is 2 h and decreases for 6 h treatment. Eventually, N-Ta2O5-2@α-Fe2O3 exhibits an enhanced photocurrent density of 3.10 mA cm–2 (4.4 times higher than that of bare α-Fe2O3), an efficiently boosted charge separation (2.0 times higher than bare α-Fe2O3), and a high chemical stability after a long-term test.
研究领域:
光电化学
·
材料科学
·
能量转换
·
催化
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）