Constructing a novel Ag nanowire@CeVO_(4) heterostructure photocatalyst for promoting charge separation and sunlight driven photodegradation of organic pollutants

摘要

Exploiting efficient and recyclable photocatalysts is a vital matter for environmental purification. Herein, cerium vanadate (CeVO_(4)) sub-microspheres and silver nanowire (AgNW)@CeVO_(4) with core-shell architecture as photocatalysts are rationally constructed by hydrothermal approach. The AgNW@CeVO_(4) photocatalyst obtained by depositing CeVO_(4) on the surface of Ag NWs possess one dimensional continuous structure, which expand the optical absorption range and reduce the band gap of CeVO_(4) photocatalyst. Moreover, the resultant AgNW@CeVO_(4) photocatalyst demonstrates superior photocatalytic performance in the degradation of rhodamine B, methylene blue, and 4-nitrophenol pollutants upon solar light irradiation, compared with pure CeVO_(4). The excellent photocatalytic activity can be ascribed to the introduction of Ag NWs, which afford rapid charge transport channels and reservoir for the electrons in the AgNW@CeVO_(4) heterostructure to promote separation of electron-hole pairs. The first-principles investigations reveal increase of adsorption energy of oxygen molecules on the CeVO_(4) surface with the presence of Ag. Meanwhile, Ag NWs can further improve the photocatalytic efficiency of the AgNW@CeVO_(4) based on the plasmonic effect. More importantly, the good structural stability and recyclability of AgNW@CeVO_(4) are observed due to the strong synergistic effect, which ensures long-term usability of photocatalyst and great promise in water purification. This work can offer valuable reference into designs and construction of Ce-based heterojunction photocatalysts for environmental remediation.