Fabrication of Ultrafine Cu2O Nanoparticles on W18O49 Ultra‐Thin Nanowires by In‐Situ Reduction for Highly Efficient Photocatalytic Nitrogen Fixation

Abstract

AbstractPhotocatalytic ammonia synthesis technology is one of the important methods to achieve green ammonia synthesis. Herein, two samples of Cu ion‐doped W18O49 with different morphologies, ultra‐thin nanowires (Cu‐W18O49‐x UTNW) and sea urchin‐like microspheres (Cu‐W18O49‐x SUMS), are synthesized by a simple solvothermal method. Subsequently, Cu2O‐W18O49‐x UTNW/SUMS is synthesized by in situ reduction, where the NH3 production rate of Cu2O‐W18O49‐30 UTNW is 252.4 µmol g−1 h−1 without sacrificial reagents, which is 11.8 times higher than that of the pristine W18O49 UTNW. The Cu2O‐W18O49‐30 UTNW sample is rich in oxygen vacancies, which promotes the chemisorption and activation of N2 molecules and makes the N≡N bond easier to dissociate by proton coupling. In addition, the in situ reduction‐generated Cu2O nanoparticles exhibit ideal S‐scheme heterojunctions with W18O49 UTNW, which enhances the internal electric field strength and improves the separation and transfer efficiency of the photogenerated carriers. Therefore, this study provides a new idea for the design of efficient nitrogen fixation photocatalysis.