In-situ room-temperature synthesis of amorphous/crystalline contact Bi2S3/Bi2WO6 heterostructures for improved photocatalytic ability

We developed a facile in-situ growth method to construct amorphous-based Bi2S3/Bi2WO6 heterostructures at room temperature. As demonstrated by HRTEM, XPS and EDX-mapping, amorphous state Bi2S3 dispersed uniformly on the surface of crystalline Bi2WO6 hollow spheres. The photocatalytic activities of prepared Bi2S3/Bi2WO6 heterostructures were evaluated by the photodegradation of RhB and TC under visible light irradiation, indicating that the introduction of appropriate amorphous Bi2S3 significantly improved the photocatalytic activity of Bi2WO6. The amorphous/crystalline contact in Bi2S3/Bi2WO6 heterostructures played a crucial role in the enhancement of photocatalytic efficiency. Based on DRS, photoluminescence spectra, photocurrent intensity, electrochemical impedance spectroscopy and OCVD measurements, it was proposed that the enhanced performance could be ascribed to increased visible light utilization, promoted separation efficiency and prolonged life time of photogenerated electron-hole pairs by the introduction of amorphous Bi2S3. This work may provide new insights into the construction of amorphous-based composited heterostructures for improving photocatalytic activity.