Investigation into the roles of interfacial H2O structure in catalytic oxidation of HCHO and CO over CuMnO2 catalysts
Maoyong Song , Chunyan Ma , Jushuang Pan , Cheng Chen , Yuanyuan Dong , Feng Yao , Fengbang Wang
DOI:10.1016/j.jes.2022.10.044
Received July 19, 2022,Revised , Accepted October 28, 2022, Available online November 08, 2022
Volume 36,2024,Pages 310-320
The rapid deactivation of cost-effective MnO2-based catalysts in humid air limits their application in practice, and the identification of the role of water in an oxidation process is significant for developing water-resistant MnO2-based catalysts. Here, CuMnO2 showed a 20.3% HCHO conversion in 10 hr at room temperature in humid air with relative humidity of 40%, but deactivated in 3 hr in dry air. The excellent activity and stability of HCHO oxidation in humid air were attributed to the positive effect of H2O on HCHO oxidation to the H2O-HOCH2OH supermolecule assemblies via hydrogen bonds formed on CuMnO2. H2O-HOCH2OH supermolecule assemblies tend to be oxidized to carbonate, which is further oxidized to CO2. Furthermore, CuMnO2 exhibited a much poorer activity of CO oxidation in humid air, but the CO conversion was still 100% in 10 hr in dry air. H2O showed a competitive adsorption effect to CO on CuMnO2. CuMnO2 could be applied in HCHO elimination in humid air and CO elimination in dry air.
