Construction of Ag nanoparticle decorated AgBr/BiVO4 shell/core structure plasmonic photocatalysts towards high photocatalytic elimination of contaminations under visible light

Abstract

Constructing highly efficient, stable and wide applicable photocatalysts with simple and controllable components to confront the environmental issue need sustained efforts. In this work, Ag nanoparticles decorated AgBr/BiVO4 shell/core heterojunction (Ag@AgBr/BiVO4) was synthesized, which showed high photocatalytic activity in removing rhodamine B (RhB, 99.1 % in 20 min) and tetracycline (TC, 94.1 % in 20 min) under visible-light irradiation. The band structure was determined based on the light absorption spectra and Mott-Schottky test. The free radical scavenger test showed the production of ·OH and ·O2− radicals which accelerated the photodegradation. Basing on these results, the enhanced photocatalytic performance can be attributed to AgBr/BiVO4 shell/core heterojunction that spatially separates the photogenerated carriers and inhibits bulk recombination. The localized surface plasmon resonance (LSPR) effect of Ag particles also improved the light absorption ability of the photocatalyst and effectively produce excess active species to accelerate the photodegradation of contaminants. The results show a coordinated regulation of Ag nanoparticles and AgBr/BiVO4 shell/core heterojunction to achieve high photocatalytic properties, the strategy of rational designing structure and energy band alignment may also offer a new insight for the applications in solar energy conversion field.