Unveiling the Position Effect of Ce within Layered MnO2 to Prolong the Ambient Removal of Indoor HCHO.

The position of Ce doping has a significant effect on ambient HCHO storage and catalytic oxidation on layered MnO2. By associating structure and performance, it is unveiled that doping Ce into the in-layered lattice of MnO2 is favorable to the generation of high-valence Mn cations, enhancing the oxidizing ability and capacity, but an opposite influence is displayed by interlayered Ce doping. From the aspect of energy minimization calculated by DFT, in-layered Ce doping is also recommended due to the decreased energies for molecule adsorption and oxygen vacancy formation. As a result, in-layered Ce-doped MnO2 displays exceptional activity in catalyzing the deep oxidation of HCHO and a fourfold higher capacity of ambient HCHO storage than pristine MnO2. The optimal oxide is combined with electromagnetic induction heating to complete the "storage-oxidation" cycle as a promising approach absolutely depending on non-noble oxides and household appliances to realize the long-acting removal of indoor HCHO at room temperature.