A Stable Plasmonic Cu@Cu2O/ZnO Heterojunction for Enhanced Photocatalytic Hydrogen Generation

The localized surface plasmon resonance (LSPR) effect has been widely utilized in photocatalysis, but most reported LSPR materials are based on noble metals of gold or silver with high chemical stability. Plasmonic copper nanoparticles that exhibit an LSPR absorbance at 600nm are promising for many applications, such as photocatalysis. Unfortunately, plasmonic copper nanoparticles are affected by serious surface oxidation in air. Herein, a novel lollipop-shaped Cu@Cu2O/ZnO heterojunction nanostructure was designed, for the first time, to stabilize the plasmonic Cu core by decorating Cu@Cu2O core-shell structures with ZnO nanorods. This Cu@Cu2O/ZnO nanostructure exhibited significantly enhanced stability than that of regular Cu@Cu2O, which accounted for the remarkably enhanced photocatalytic H-2 evolution rate through water splitting, relative to pristine ZnO nanorods, over an extended wavelength range due to the plasmonic Cu core.