Mesoporous -Al₂ O₃ Supported Mn-Ce-Co Ternary Oxides for the Efficient Plasma-Catalytic Oxidation of Formaldehyde

Coupling low-temperature plasma technology with catalysts can significantly enhance air purification efficiency and mitigate the generation of secondary pollutants. In this study, mesoporous gamma-Al2O3 supported Mn-Ce-Co ternary oxides were introduced into a widely employed tubular dielectric barrier discharges (DBD) reactor for indoor air purification. The plasma-catalytic degradation of HCHO exhibited the following degradation efficiency order: Mn-Ce-Co/gamma-Al2O3 > Mn/gamma-Al2O3 > Mn-Ce/gamma-Al2O3 > Co/gamma-Al2O3 > gamma-Al2O3 > Ce/gamma-Al2O3 > Plasma. When compared to plasma treatment alone, the catalyst resulted in a remarkable 1.8-fold enhancement under conditions of 3.0kV, 25(degrees)C, 60% RH. Additionally, the concentrations of the by-products O-3 and NOx were significantly reduced by 88.2% and 93.3%, respectively. The synergistic interaction between Mn, Ce and Co oxides facilitated the formation and transportation of surface-reactive oxygen species, thereby contributing to the thorough oxidation of HCHO and organic intermediates during the plasma-catalytic process. Moreover, the high specific surface area offered by mesoporous materials enhanced the adsorption and catalytic activity towards HCHO.