Copper tungstate (CuWO₄) nanoflakes coupled with cobalt phosphate (Co-Pi) for effective photoelectrochemical water splitting

Photoelectrochemical (PEC) water splitting provides us a green way to convert and utilize solar energy. In this work, Co-Pi was electrochemically deposited onto CuWO₄ nanoflakes (NFs) via a cyclic voltammetry (CV) method to enhance the photocatalytic performance of CuWO₄ toward PEC water splitting. The results demonstrated that the photocurrent density as well as the charge-transfer efficiency was improved within the entire potential range. Besides, the CuWO₄/Co-Pi exhibited an enhanced stability over the bare CuWO4 in the phosphate buffer solution (pH 7) and an extremely high Faradaic efficiency (ca. 96%). Our work reveals that combination of CuWO₄ with Co-Pi is a feasible way to further enhance the performance of CuWO₄ photoanode toward PEC OER.