Zhang Tao, Wu Huiqing, Li Naihan, Li Chen, Wang Zhiqiang, Liu Guanghui, Xu Song, Wei Meng, Su Jinzhan, Cui Jiehu
School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, Henan 450046, China.
International Research Centre for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
Inorg Chem. 2025 Apr 28;64(16):8270-8282. doi: 10.1021/acs.inorgchem.5c00587. Epub 2025 Apr 16.
Bismuth vanadate (BiVO) is a potential photoelectrode for photoelectrochemical (PEC) applications. Nevertheless, the rapid charge recombination and sluggish water oxidation kinetics greatly limit the PEC activity. To address these drawbacks, this study developed a cooperative modification strategy with simultaneous La doping and amorphous cobalt-phytate compound (Co-phy) as a cocatalyst on BiVO to raise the PEC performance. La doping increased the donor density, and the decoration of the Co-phy cocatalyst expedited water oxidation kinetics and further improved the utilization efficiency of charge carriers. As a result, the constructed hybrid photoelectrode (La-BVO/Co-phy) generated a photocurrent of 2.12 mA·cm at 1.23 V vs RHE, about 4.8 times that of the pristine BiVO photoelectrode (0.44 mA·cm). Moreover, a significant reduction in onset potential and prominent improvement in conversion efficiency, stability, and charge separation efficiency were achieved for the synergistically modified photoanode. Furthermore, a profound exploration on the charge dynamics disclosed increased carrier density, decreased charge recombination, and enhanced charge transfer kinetics as a consequence of the synchronized effect of La doping and Co-phy cocatalyst, which greatly contributed to the elevated PEC activity. This work introduces a practical route to fabricating BiVO-based photoelectrodes for solar water splitting applications.
钒酸铋（BiVO）是一种用于光电化学（PEC）应用的潜在光电极。然而，快速的电荷复合和缓慢的水氧化动力学极大地限制了PEC活性。为了解决这些缺点，本研究开发了一种协同改性策略，在BiVO上同时进行La掺杂和使用无定形植酸钴化合物（Co-phy）作为助催化剂，以提高PEC性能。La掺杂增加了施主密度，Co-phy助催化剂的修饰加快了水氧化动力学，并进一步提高了载流子的利用效率。结果，构建的复合光电极（La-BVO/Co-phy）在相对于可逆氢电极（RHE）为1.23 V时产生了2.12 mA·cm的光电流，约为原始BiVO光电极（0.44 mA·cm）的4.8倍。此外，对于协同改性的光阳极，起始电位显著降低，转换效率、稳定性和电荷分离效率显著提高。此外,对电荷动力学进行的深入探索表明，由于La掺杂和Co-phy助催化剂的同步作用，载流子密度增加，电荷复合减少，电荷转移动力学增强，这极大地促进了PEC活性的提高。这项工作为制造用于太阳能水分解应用的BiVO基光电极引入了一条实用途径。
