Surface gallium oxide hydroxide species adsorbing carbon dioxide to enhance the photocatalytic activity of silver-loaded calcium titanate for carbon dioxide reduction with water

Abstract

Photocatalytic conversion of carbon dioxide (CO₂) has attracted considerable attention as a new method to build a carbon cycle. Particularly, photocatalytic reduction of CO₂ using water as an electron and proton donor to yield carbon monoxide (CO) is quite valuable but challenging, where enhancement of CO₂ adsorption on the photocatalyst surface may contribute to increasing the photocatalytic reaction rate. In this viewpoint, the surface modification was examined for an Ag/CTO photocatalyst that can promote CO₂ reduction with water selectively, i.e., an Ag/GaOOH/CTO photocatalyst was prepared by a step-by-step loading method. As a result, the GaOOH species deposited on CaTiO₃ with Ag NPs endowed the photocatalyst with enhanced CO₂ adsorption properties to increase the CO yield more than 5 times. This short paper provides one of the strategies to improve the photocatalytic properties of CO₂ reduction with water.