Synthesis of CuI/Sn-ZnO Based p-n Heterojunction Photoanode for Photoelectrochemical Water Splitting

Abstract

Harvesting energy from the sun is contemplated to be one of the notable choices to meet the ever-increasing energy demands of the current progressive society. Photoelectrochemical splitting of water (PEC-WS) into H2 and O2 turned out to be a constructive strategy to overcome the prevailing energy crunch. In this present work, ZnO is doped with different concentrations of Sn and coupled with CuI to construct a p-n heterostructure. Compared to bare ZnO, CuI/5% Sn-ZnO manifested better absorbance in the visible region, enhanced photocurrent density (1.08 mA/cm2), more negative flat band potential, high charge carrier density and least semi-circular arc radius in Nyquist plot. Hence, the present work delineates p-n heterostructure and their nano-engineering opens a potential route for fabricating light-harvesting photoelectrodes to be used for an improved PEC-WS applications.