Core-Shell Composites Based on Multiwalled Carbon Nanotubes and Cesium Tungsten Bronze to Realize Charge Transport Balance for Photocatalytic Water Oxidation

摘要

Core-shell composite photocatalysts based on multiwalled carbon nanotubes (MWCNTs) and Cs2W3O10 are first synthesized by an ion-directing method. Cs+ is preadsorbed on the surface of MWCNTs by electrostatic forces and directs the crystallization of Cs2W3O10 to form a uniform layer on the surface of the MWCNTs. This core-shell arrangement of a MWCNT@Cs2W3O10 composite photocatalyst with a 15nm thick Cs2W3O10 layer allows the charge transport balance to be achieved in the photocatalytic water oxidation process and confers a high photoactivity. Other reference composite photocatalysts that deviate from this balance result in deteriorated photoactivity. The established synthetic method provides a new method for the design and synthesis of composite photocatalysts, and the realization of charge transport balance is helpful to understand the nature of the enhancement of photoactivity in photocatalytic processes.