Pai Hao, Kuo Tsung-Rong, Chung Ren-Jei, Kubendhiran Subbiramaniyan, Yougbaré Sibidou, Lin Lu-Yin
Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan.
International PhD Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei 11031, Taiwan; Graduate Institute of Nanomedicine and Medical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei 11031, Taiwan.
J Colloid Interface Sci. 2022 Oct 15;624:515-526. doi: 10.1016/j.jcis.2022.05.169. Epub 2022 Jun 1.
Doping heteroatoms and decorating co-catalyst are intensively applied to improve photocatalytic ability of BiVO. In this study, it is the first time to design W-doped BiVO coupling MIL-101(Fe) as photocatalyst for water oxidation using electrodeposition and hydrothermal processes. Similar system with Mo as dopant has been reported, but the dopant plays important roles on electrochemical performance. It is worthy to study the efficient system with different dopant. Doping amount of W is optimized to achieve high carrier density without creating serious recombination sites. MIL-101(Fe) is decorated on W-doped BiVO to suppress surface recombination, create accessible active sites and improve water oxidation kinetics. Optimized W-doped BiVO/MIL-101(Fe) electrode shows a high photocurrent density of 4.00 mA/cm at 1.23 V versus reversible hydrogen electrode (V) under air mass 1.5-global simulated light illumination without hole scavenger in electrolyte, due to large electrochemical surface area, high carrier density and small charge-transfer resistance. The W-doped BiVO and BiVO electrodes merely show photocurrent densities of 2.96 and 1.72 mA/cm at 1.23 V, respectively. Photocurrent retention higher than 95.5% is obtained for W-doped BiVO/MIL-101 (Fe) electrode under continuous illumination for 6300 s, suggesting lasting photocatalytic ability of this novel W-doped BiVO/MIL-101(Fe) electrode.
掺杂杂原子和修饰助催化剂被广泛应用于提高BiVO的光催化能力。在本研究中，首次采用电沉积和水热法设计W掺杂的BiVO与MIL-101(Fe)耦合作为水氧化光催化剂。已报道过类似的以Mo作为掺杂剂的体系，但该掺杂剂对电化学性能起着重要作用。研究具有不同掺杂剂的高效体系是值得的。优化W的掺杂量以实现高载流子密度，同时不产生严重的复合位点。在W掺杂的BiVO上修饰MIL-101(Fe)以抑制表面复合，产生可及的活性位点并改善水氧化动力学。优化后的W掺杂BiVO/MIL-101(Fe)电极在空气质量1.5-全球模拟光照下，相对于可逆氢电极（V）在1.23 V时，在电解质中无空穴清除剂的情况下显示出4.00 mA/cm的高光电流密度，这归因于大的电化学表面积、高载流子密度和小的电荷转移电阻。W掺杂的BiVO电极和BiVO电极在1.23 V时分别仅显示出2.96和1.72 mA/cm的光电流密度。W掺杂BiVO/MIL-101(Fe)电极在连续光照6300 s下获得高于95.5%的光电流保留率，表明这种新型W掺杂BiVO/MIL-101(Fe)电极具有持久的光催化能力。
