One step in situ synthesis of core–shell structured Cr2O3:P@fibrous-phosphorus hybrid composites with highly efficient full-spectrum-response photocatalytic activities

Abstract

Making full use of solar energy and achieving high charge separation efficiency are critical factors for the photocatalysis technique. In this work, we report core–shell structured fibrous phosphorus (f-P) coated P-doped Cr₂O₃ (Cr₂O₃:P@f-P) hybrid composites with a strong optical absorption in the full region of 200–2600 nm. The Cr₂O₃:P@f-P hybrid composites exhibit a record photocatalytic efficiency under UV, visible and near-infrared light irradiation, demonstrating as promising photocatalysts for the full utilization of solar energy. Systematical investigations combining experimental and theoretical work show that P doping modifies the electronic band structures and creates defective levels in the forbidden gap of Cr₂O₃ which extends the optical absorption to the visible and near-infrared regions. Highly crystalline fibrous phosphorus in situ grown on the Cr₂O₃ particles constructs a core–shell hybrid structure which guarantees intimate interfacial contact between f-P and Cr₂O₃:P and facilitates the separation of photogenerated electron–hole pairs. This study develops a promising system based on earth abundant element P to utilize the overall spectrum of sunlight for photochemical applications.