Role of Structural Defects in MnOx Promoted by Ag Doping in the Catalytic Combustion of Volatile Organic Compounds and Ambient Decomposition of O3

Manganese oxides are prominent candidates for catalytic oxidation of VOCs or ambient decomposition of O3 individually. Here, we compared various preparation methods to create a defect-enriched Ag-MnOx nanocomposite that exhibits remarkably multifunctional activity in VOC combustion and ozone decomposition. Ag+ ions were well-dispersed in the micro tunnels of Ag-MnOx-H via hydrothermal replacement of the original K+ ions; this catalyst’s benzene combustion efficiency (T90%=216 oC at space velocity=90000 mLh-1g-1) was comparable to that of typical noble metal catalysts. Moreover, the decomposition of ozone over the Ag-MnOx-H catalyst (space velocity=840000 mLh-1g-1) under RH=60% was above 90%, indicating that it is a promising material for ozone elimination in practical application. The local structure results indicated that silver incorporation via the hydrothermal method facilitates formation of non-stoichiometric defects in the MnOx matrix. The large number of active oxygen species related to O vacancies...