Thermally Stable SiO2 from Coal Gangue-Supported CuOx and CeO2 Active Sites Ensemble as Catalysts for Efficient H2 Purification

Utilization of coal gangue holds immense significance in eliminating negative impacts on the environment. Mineral components in the coal gangue can be exploited as catalyst support to address the issues of reducing catalyst costs and enhancing catalytic performance. Here, we developed the CuCe/SiO₂ catalysts (SiO₂ derived from coal gangue) to achieve complete conversion of CO in the temperature range from 115 to 215 °C with long-term stable operation for 80 h in preferential CO oxidation. In situ/operando spectroscopy and density functional theory calculations reveal that the distribution of highly dispersed CuO_x species on the surface of CeO₂ with oxygen vacancies improves the adsorption of CO and O₂ molecules, and the d-band center is relocated closer to the Fermi level as well as the CeO₂ crystalline features are changed after CO and O₂ adsorption. Furthermore, thermally stable SiO₂ protects the active species, thus facilitating preferential CO oxidation. These findings will inspire the development of effective approaches for the reuse of coal gangue.