Fabrication of chrysanthemum-like CdSe/bulk WC: A novel Schottky-junction photocatalyst for improving photocatalytic hydrogen production

摘要

The developments of direct synthesis for shape-controlled and high-efficiency photocatalysts are exceed-ingly exigent for achieving clean hydrogen (H-2) energy by solar light. In this work, we developed facile synthesis to construct a novel chrysanthemum-like cadmium selenide (CdSe)/bulk tungsten carbide (WC) Schottky-junction photocatalyst. The characteristic results for the component, microstructure and chemical state of photocatalyst revealed that chrysanthemum-like CdSe was intimately decorated onto the bulk WC surface using an ultrasonic-hydrothermal method. The photocatalytic results indicated that the optimal sample obtained the maximum H-2 evolution amount (2711.9 mu mol g(-1) in 5 h) under visible light irradiation, which was 7.4 times higher than that of chrysanthemum-like CdSe. The observably improved H-2 evolution activity was attributed to the ample active sites, the lower onset overpotential (-0.25 V) and the slower surface charge recommendation rate (0.011 s(-1)). Meanwhile, intimate contact at the CdSe/WC interface could engender synergistic effect and actuate the formation of Schottky barrier, which effectively facilitated the reduction of water to H-2. This study uncovers an easily available synthesis for shape-controlled CdSe and in-depth explores the design of CdSe-based Schottky-junction photocatalyst for promoting photocatalytic H-2 evolution performance. (C) 2021 Elsevier B.V. All rights reserved.