Enhancement of photocurrent and photocatalytic activity of ZnO hybridized with graphite-like C3N4

Abstract

A ZnO photocatalyst was hybridized with graphite-like C₃N₄via a monolayer-dispersed method. After hybridization with C₃N₄, the photocurrent of ZnO was enhanced by 5 times under UV irradiation and a photocurrent under visible light irradiation was observed. The photocatalytic activity of C₃N₄/ZnO under UV irradiation was increased by 3.5 times, the visible light photocatalytic activity was generated and the photocorrosion of ZnO was suppressed completely after ZnO was hybridized with C₃N₄. The enhancement in performance and photocorrosion inhibition under UV irradiation was induced by the high separation efficiency of photoinduced holes from ZnO to the HOMO of C₃N₄. Under visible light irradiation, the electron excited from the HOMO to the LUMO of C₃N₄ could directly inject into the CB of ZnO, making C₃N₄/ZnO present visible light photocatalytic activity. The optimum synergetic effect of C₃N₄/ZnO was found at a weight ratio of 3%, which corresponded to a monolayer dispersion of C₃N₄ on the surface of ZnO.