Preparation of cypress leave-like Ag2WO4/BiVO4 heterojunctions with remarkably enhanced photocatalytic activity

Cypress leave-like Ag2WO4/BiVO4 heterojunctions were successfully prepared by a two-step synthesis technique. To confirm the successful construction of Ag2WO4/BiVO4 heterojunctions, high-resolution transmission electron microscopy (HRTEM), X-ray powder diffraction (XRD) and energy dispersive spectroscopy (EDS) tests were performed. Surface photovoltage spectroscopy (SPS) was employed to study the separation of photoactivated carriers. Photocatalytic destruction of rhodamine B (RhB) by the samples was evaluated under UV light irradiation. The evaluation manifests that the Ag2WO4/BiVO4 heterojunctions exhibit higher photocatalytic degradation ability for RhB than the single BiVO4 and Ag2WO4. The photocatalytic performance of Ag2WO4/BiVO4 heterojunctions is 4 and 2 times of that of BiVO4 and Ag2WO4, respectively. The excellent photocatalytic performance of the Ag2WO4/BiVO4 photocatalyst is attributable to the formation of heterojunctions, which greatly expedites the separation of photo-induced carriers and the production of O2−.