Copper phosphosulfides as a highly active and stable photocatalyst for hydrogen evolution reaction

• Published in: Applied catalysis. B, Environmental Environmental, 2020-09, Vol.273, p.118927, Article 118927
• Main Authors: Zhang, Xiandi, Min, Kyung-Ah, Zheng, Weiran, Hwang, Jeemin, Han, Byungchan, Lee, Lawrence Yoon Suk
• Format: Article
• Language: English
• Subjects: Catalysts; Copper; copper phosphosulfide; Copper sulfides; Crystal structure; Cups; DFT calculations; Energy conversion; First principles; Free energy; Gibbs free energy; Hydrogen; Hydrogen evolution reaction; Hydrogen evolution reactions; Hydrogen-based energy; Phosphides; Photocatalysis; Sulfide; Transition metals; Wet chemical approach
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.118927

[Display omitted] •Two copper phosphosulfides (CuS|P and Cu3P|S) are synthesized using conventional solid-state and novel wet chemical approaches.•The new structure, copper phosphosulfide, exhibits an excellent performance in photocatalytic hydrogen evolution reaction (HER).•The phosphosulfide structure shifts the Gibbs free energy of H2 adsorption close to 0 eV.•The HER activity is correlated to the formation level of phosphosulfide structure that considerably increases the number of active sites. Transition-metal phosphosulfides (TMPSs) have recently shown outstanding electrocatalytic performances toward hydrogen evolution reaction (HER), superior to the sulfide and phosphide counterparts. However, there are only limited TMPSs available due to the synthetic challenge. Herein, we demonstrate a novel synthetic approach for copper phosphosulfide (CuPS) and the first application in photocatalytic HER. Based on the thermodynamic considerations of starting materials, two synthetic routes are designed to obtain two distinct crystal structures (CuS|P and Cu3P|S). Dramatically enhanced photocatalytic HER activities are achieved for both Cu3P|S (2,085 μmol g-1 h-1) and CuS|P (976 μmol g-1 h-1) without using co-catalysts. First-principles calculations unveil the underlying mechanism for the improved HER activity, in which the Gibbs free energy of hydrogen adsorption approaches close to 0 eV and the number of active sites considerably increases with the formation of CuPS structure. This work provides new insight and design principle on preparing TMPSs for high-performance energy conversion applications.