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 in-layered lattice of MnO₂ is favorable to generation of high-valence Mn cations causing enhancement of oxidizing ability and capacity, but an opposite influence is displayed by inter-layered 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 performs an exceptional activity in catalyzing 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 “storage-oxidation” cycle, as a promising approach absolutely depending on non-noble oxides and household appliances to realize long-acting removal of indoor HCHO at room temperature.

Schematic diagram and performance evaluation of manganese oxide electromagnetic induction driven 'storage-oxidation' cycle