CoP electrodeposited on TiO 2 nanorod arrays as photoanode for enhanced photoelectrochemical water splitting

Abstract It is of great significance to design photoelectrodes with high carrier separation and transport efficiency in photocatalytic water separation systems. In this study, we used a simple electrochemical deposition method to regulate the load of co‐catalyst CoP on TiO 2 nanorods to improve the photoelectrochemical properties. The photocurrent density of TiO 2 /CoP (20) photoanode at 1.23 V increases to 1.57 mA/cm 2 , which is 3.4 times that of original TiO 2 . Long‐term photoelectrolysis reveals that this electrode has excellent stability. Mechanistic studies support the role of CoP nanoparticles in improving photoelectrochemical property and imply that the excellent photoelectrochemical property of TiO 2 /CoP photoanode is mainly ascribed to the suppress of surface photogenerated electrons and holes recombination due to the construction of built‐in electric field between TiO 2 and CoP.