Highly Efficient Rutile TiO2 Endowed by Electron-Capturing Center and Plasma Effect for Enhanced Solar Water Splitting

Abstract

Although a deep electron trap of rutile TiO₂ has been proven recently, studies on how to reduce its influences have not been reported. To inhibit the deep electron trap and long-living hole of rutile TiO₂, a remarkable nanorod photocatalyst, TiO₂(R)-NiCu, with an electron-capturing center and plasma center, is developed. Using the remarkable nanorod photocatalyst, the photocatalytic hydrogen evolution rate can reach 24.4 mmol·g^–1·h^–1, which is 61 times that of the reference catalyst. The experimental and theoretical simulation shows that Ni, as the electron-capturing center, can transfer the electrons in the electron trap, while Cu, as the plasma center, can supply hot electrons to the conduction band and stimulate them to recombine with holes. The synergistic effect of Ni and Cu inhibits the deep electron trap and long-living hole of rutile TiO₂ and enhances the charge transfer efficiency, resulting in significantly improved photocatalytic activity.