Boosting carrier separation in Ag/AgBr/halloysite-nanotubes composites for enhanced photocatalytic performance

Abstract The practical application of Ag/AgBr is restricted by the photocorrosion problem and rapid combination of the plasmon-induced electron-hole pairs during photoreactions. Herein, we introduced halloysite-nanotubes (HNTs) into Ag/AgBr system to fabricate a series of novel Ag/AgBr/HNTs composites. The degradation of Rhodamine B and killing of gram-negative bacterium Escherichia coli under illumination was employed to test the photocatalytic activity of these modified silver-based catalysts. The results showed that Ag/AgBr/HNTs composites processed excellent visible-light-driven disinfection activity, splendid photocatalytic performance and good catalytic stability. Based on the experimental observations and characterization results, the main reasons were as follows: first, HNTs serves as a support in the composite and prevent the decomposition of Ag/AgBr particles; secondly, the charged surface of HNTs can effectively boost the separation of electron-hole pairs and promote the adsorption of reactants. In a word, this work could provide a new approach to design highly efficient photocatalyst for water purification.