Synthesis of ZnO/Bi2S3 Core/Shell Nanowire Array Photoanodes for Photocathodic Protection of Stainless Steel

Abstract

Nanocrystalline Bi2S3 shells were conformally deposited on ZnO nanowire arrays via a successive ionic layer adsorption and reaction approach. Microstructure, optical, and electric properties of the as-prepared ZnO/Bi2S3 core/shell nanowire heterostructures were thoroughly investigated using various characterization and electrochemical methods. Compared with the pristine ZnO photoanode (−734 mV and 0.57 mA·cm−2), the ZnO/Bi2S3 photoanode with a type-II heterojunction exhibited a more negative shift in the coupled open circuit potential (−862 mV) and a higher photocurrent density (2.92 mA·cm−2), achieving more effective photocathodic protections for the coupled 304 stainless steel under solar illumination.