Construction, characterization, photochemical properties and the possible mechanism of Ag/AgBr/Ag3BiO3 composites

Abstract

Abstract The AgBr/Ag 3 BiO 3 composite photocatalyst was fabricated by one-step hydrothermal route. The as-obtained sample was systematically characterized by X-ray diffraction (XRD), UV–Vis diffuse reflectance (DRS), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscope (SEM) and photoluminescence (PL) measurements. The photocatalytic activity was evaluated through degradation of the Methylene blue (MB) under visible light irradiation. Results illustrated that the Ag/AgBr/Ag 3 BiO 3 -5 (Ag/AgBr/ABO-5) exhibited the optimal performance, and the first-order rate constant ( k obs ) value of Ag/AgBr/ABO-5 was about 8.4 and 17.5\u2009~\u2009fold than that of bare AgBr and Ag 3 BiO 3 , respectively. Trapping agent experiments indicated that the h + and •O 2 − were dominative species for MB degradation. The results of PL proved that the electrons and holes can be separated effectively in the Ag/AgBr/ABO-5. In this work, type-I heterojunction was rendered to explain the transferring process, thus significantly enhancing photocatalytic reactivity of the composites. Graphic abstract