A novel Cu single-atom catalyst prepared through the adsorption characteristics of MoS2: from preparation to application†
Abstract
Single-atom catalysis is one of the most popular methods to treat wastewater at present. However, how to improve the catalyst performance without aggregation and broaden the application range is the main problem that puzzles the further development of this technology. Herein, a novel method for the preparation of single-atom catalysts was proposed to solve this problem. Cu loaded on flower-like MoS2 layers with atomic dispersion was obtained through the adsorption of metal ions by MoS2 and high-temperature annealing in the presence of thiourea. The atomic level dispersion of Cu was confirmed by high-angle annular dark field scanning transmission electron microscopy and X-ray absorption fine structure. The electronic and coordination structures of central Cu were revealed by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). Notably, the removal efficiency of methylene blue by the catalyst was nearly 80% even at a pH of 11.0, and such excellent performance could be attributed to the synergistic effect with MoS2. Furthermore, the application potential of the catalyst was validated through experiments in a reactor. In conclusion, this study not only presents innovative concepts for the design of single-atom catalysts but also provides valuable insights into their application in aquatic environments.