| Institution: | 1. College of Chemistry and Chemical Engineering, State Key Laboratory of Power Transmission Equipment &, System Security and New Technology, Chongqing University, 174 Shazheng Street, Shapingba District, 400044 Chongqing City, P. R. China
These authors contributed equally to this work.;2. College of Optoelectronic Engineering, Chongqing University, 400044 Chongqing, P. R. China;3. College of Chemistry and Chemical Engineering, State Key Laboratory of Power Transmission Equipment &, System Security and New Technology, Chongqing University, 174 Shazheng Street, Shapingba District, 400044 Chongqing City, P. R. China |
| Abstract: | Cu2O is an ideal p-type material for photo-electrochemical (PEC) hydrogen evolution, although serious electron–hole recombination and photocorrosion restrict its further improvement for PEC activity. In this work, CeO2 nanoparticles (NPs) self-assemble on the surface of Cu2O octahedra, thus successfully forming a Cu2O/CeO2 structure in which p–n heterojunctions and micro-mesocrystals (m-MCs) work together. The optimum Cu2O/CeO2 composite, without the use of any cocatalyst, exhibits a fivefold higher photocurrent density (4.63 mA cm−2 at 0 V vs. the reversible hydrogen electrode) than that of Cu2O octahedra, which is better than most Cu2O-based photocathodes without cocatalyst and even comparable with advanced Cu2O-based photocathodes. The hydrogen production of the optimal Cu2O/CeO2 (Faradaic efficiency of ∼100 %) is 17.5 times higher than that of pure Cu2O octahedra, and the photocurrent shows almost no decay under the 12 h stability test. The delicately designed Cu2O/CeO2 structure in this work provides reference and inspiration for the design of cathodes materials. |
