Ce-doped MIL-101(Fe)-derived CoOx/MnOx@Fe2O3 catalysts for photothermal coupled catalytic degradation of acetone and NO

The technology of photothermal catalytic degradation of acetone and conversion of nitrogen monoxide (NO) not only reduces energy consumption compared to traditional thermal catalytic oxidation technology but also improves degradation efficiency, effectively overcoming the limitations of single photocatalytic or thermal catalytic technology. This paper aims to control the lattice oxygen activity and oxygen vacancy concentration of the catalyst by optimizing the manganese-cobalt (Mn–Co) molar ratio and modifying the catalyst with Ce doping, thereby enhancing its photocatalytic and thermal catalytic performance for the degradation of acetone and NO. At 240 °C, when the Mn–Co molar ratio is 4:2, the CoO_x/MnO_x@Fe₂O₃-2 catalyst exhibits good catalytic activity for both acetone and NO, with conversion rates of 52% and 63.8% for acetone and NO, respectively. Based on the optimization of the Mn–Co molar ratio, Ce was doped into the CoO_x/MnO_x@Fe₂O₃-2 sample using the co-precipitation method to synthesize samples with different Ce doping amounts. The sample of CeO₂/CoO_x/MnO_x@Fe₂O₃-2-0.25 (n_Mn-Co:n_Ce = 1:0.25) shows the highest catalytic performance compared with the other samples, with the conversion of acetone and NO reaching 60% and 70%, respectively, at 240 °C. Additionally, the intrinsic mechanism under photothermal synergy is based on the Mars-van Krevelen redox cycle theory.