Abstract We demonstrate the cobalt phosphate (Co-Pi) modified 1-D WO3/BiVO4 nanowire heterojunction photoanode as oxygen evolution catalyst for photoelectrochemical (PEC) water splitting application. WO3 nanowires were prepared by flame vapor deposition (FVD) process and BiVO4 nanoparticles were spin-coated on top of WO3 nanowires. In order to improve oxygen evolution kinetics, WO3/BiVO4 heterojunction photoanode was modified by photo-assisted electrodeposition of Co-Pi. Co-Pi improve the PEC water oxidation efficiency of 1 D-WO3/BiVO4 by reducing the charge recombination, facilitating the hole transfer and reducing the overpotential of oxygen evolution reaction. The optimum amount of Co-Pi for high photocurrent density was proposed. The loaded Co-Pi has enhanced the overall PEC performance showing largely shifted onset potential (∼450 mV) with significantly increased photocurrent (2.7 times at 1.23 V vs. RHE). The prepared composite photoanode of 1-D WO3/BiVO4/Co-Pi shows the higher incident photon to current efficiency and applied bias photon-to-current efficiency than without Co-Pi loading. We obtain the highest level of PEC performance with WO3/BiVO4/Co-Pi heterojunction composite photoanode which is based on 1-D framework of WO3 prepared by facile, rapid and economical FVD in this study.

中文翻译：

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火焰气相沉积制备磷酸钴和BiVO4改性一维WO3的光电化学析氧

摘要 我们展示了磷酸钴 (Co-Pi) 修饰的一维 WO3/BiVO4 纳米线异质结光阳极作为用于光电化学 (PEC) 水分解应用的析氧催化剂。通过火焰气相沉积（FVD）工艺制备 WO3 纳米线，并将 BiVO4 纳米颗粒旋涂在 WO3 纳米线的顶部。为了提高析氧动力学，WO3/BiVO4 异质结光电阳极通过 Co-Pi 的光辅助电沉积改性。Co-Pi 通过减少电荷复合、促进空穴转移和降低析氧反应的过电位来提高 1 D-WO3/BiVO4 的 PEC 水氧化效率。提出了用于高光电流密度的最佳 Co-Pi 量。负载的 Co-Pi 增强了整体 PEC 性能，显示出起始电位大幅移动（~450 mV），光电流显着增加（1.23 V 时为 RHE 时的 2.7 倍）。制备的一维 WO3/BiVO4/Co-Pi 复合光阳极显示出比没有 Co-Pi 负载更高的入射光子电流效率和施加偏置光子电流效率。在本研究中，我们使用 WO3/BiVO4/Co-Pi 异质结复合光阳极获得了最高水平的 PEC 性能，该复合光阳极基于 WO3 的一维框架，通过简便、快速和经济的 FVD 制备。