Enhanced Photocatalytic Reaction at Air-Liquid-Solid Joint Interfaces
Xia Sheng†,Zhen Liu†,Ruosha Zeng†,Liping Chen†,Xinjian Feng*,†（封心建）,and Lei Jiang‡
†College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People’s Republic of China
‡School of Chemistry and Environment, Beihang University, Beijing 100191, People’s Republic of China
J. Am. Chem. Soc.2017,139, 12402--12405
Semiconductor photocatalysis has long been considered as a promising approach for water pollution remediation. However, limited by the recombination of electrons and holes, low kinetics of photocatalysts and slow reaction rate impede large-scale applications. Herein, we addressed this limitation by developing a triphase photocatalytic system in which a photocatalytic reaction is carried out at air-liquid-solid joint interfaces. Such a triphase system allows the rapid delivery of oxygen, a natural electron scavenger, from air to the reaction interface. This enables the efficient removal of photogenerated electrons from the photocatalyst surface and minimization of electron-hole recombination even at high light intensities, thereby resulting in an approximate 10-fold enhancement in the photocatalytic reaction rate as compared to a conventional liquid/solid diphase system. The triphase system appears an enabling platform for understanding and maximizing photocatalyst kinetics, aiding in the application of semiconductor photocatalysis.