The serious recombination of photogenerated carriers and the photochemical corrosion of the electrode extremely restricted its photoelectrochemical (PEC) performance, which could not reach the theoretical photocurrent intensity. However, so far, there are few comprehensive reports on the mechanism of corrosion inhibition and stability improvement of electrodes in photocatalytic degradation. In this paper, BiVO₄/Cu₂O heterojunction modified by Cobalt-phosphate (Co-Pi) co-catalyst was successfully prepared to address the aforementioned issues. Co-Pi completed the holes capture and release process through the change of its own chemical state (Co^2+/3+→Co⁴⁺→Co^2+/3+), and also affected the energy band bending of the BiVO₄/Cu₂O heterojunction. In addition, the effect mechanism of the Co-Pi film thickness on the PEC performance of the photoanode was systematically discussed in this report. When the deposition amount was 0.05 C∙cm^-2, the photocurrent density reached 2.22 mA∙cm^-2 at 1.23 V (vs. RHE), which was 2.8 times that of bare BiVO₄. The LSV curves, EIS and UV-vis absorption spectra reveal the enhanced PEC performance and light stability of the prepared electrode materials. When it is applied to photocatalytic degradation of organic pollutants, BiVO₄/Cu₂O/0.05 Co-Pi shows high activity and potential for MB and CIP degradation, and is expected to be stably applied to the field of photocatalytic degradation of refractory organic pollutants in water.

光生载流子的严重复合和电极的光化学腐蚀极大地限制了其光电化学性能，无法达到理论光电流强度。但是，迄今为止，关于光催化降解中的腐蚀抑制机理和电极稳定性提高的综合报道很少。为解决上述问题，成功制备了磷酸钴（Co-Pi）助催化剂改性的BiVO ₄ / Cu ₂ O异质结。Co-Pi通过改变其自身的化学状态（Co ^{2 + / 3 +} →Co ⁴⁺ →Co ^{2 + / 3 +）}完成了空穴捕获和释放过程），也影响了BiVO ₄ / Cu ₂ O异质结的能带弯曲。此外，本报告系统地讨论了Co-Pi膜厚度对光电阳极PEC性能的影响机理。当沉积量为0.05 C∙cm ^-2时，光电流密度在1.23 V（vs. RHE）下达到2.22 mA∙cm ^-2，是裸BiVO _4的2.8倍。LSV曲线，EIS和UV-vis吸收光谱揭示了所制备电极材料的增强的PEC性能和光稳定性。用于有机污染物的光催化降解时，BiVO ₄ / Cu ₂O / 0.05 Co-Pi表现出很高的活性和MB和CIP降解的潜力，并有望稳定地应用于水中难降解有机污染物的光催化降解领域。