Synthesis of Au‐decorated WO3 nanoplates for simultaneous oxidation of RhB and reduction of Cr(VI) under visible light irradiation

Abstract

AbstractTungsten oxide (WO3) nanoplates were synthesized by a simple chemical precipitation technique. These nanoplates were decorated by Au nanoparticles via photoreduction route. The obtained samples were characterized by field emission scanning electron microscopy, X‐ray diffractometry and UV–vis diffuse reflectance spectroscopy to investigate their morphological, structural and optical properties. The SEM images show the plate morphology with the size in the range of 50–150 nm, their thickness ≈10 nm; spherical‐like Au nanoparticles ≈20 nm were attached to the surface of the WO3 plates. These materials were applied for the simultaneous photocatalytic degradation of Rhodamine B (RhB) and Cr(VI) under visible light. Due to the efficient separation of photoinduced charge carriers and the enhanced visible light absorption ability, the photocatalytic performance of Au‐decorated WO3 nanoplates was higher. The main active species responsible for the photodegradation reactions were identified by different scavengers and a photocatalytic mechanism was proposed. This work represents that WO3 nanoplates are a promising candidate for the degradation of organic and inorganic pollutants from the industrial wastewater under sun light exposure.