Plasma‐Catalytic Reactions for Soot Oxidation on VOx/M (M=KIT‐6, SBA‐15 and SiO2) Catalysts: Influence of Pore Structure

Abstract In this work, the effect of pore structure for VO x /M (M=KIT‐6, SBA‐15 and SiO 2 ) catalysts on plasma‐catalytic soot oxidation was investigated. The combination of VO x /KIT‐6 and plasma shows the highest soot oxidation rate, followed by VO x /SBA‐15‐packed and VO x /SiO 2 ‐packed plasma reactor. The soot oxidation rate of 97.4 % and the energy efficiency of 0.95 g kWh −1 can be achieved in plasma‐catalytic soot oxidation over VO x /KIT‐6 at 30 th min and 20 W. The catalysts were characterized by N 2 adsorption‐desorption, X‐ray diffraction (XRD), transmission electron microscopy (TEM), hydrogen temperature‐programmed reduction (H 2 ‐TPR) and X‐ray photoelectron spectroscopy (XPS). The results illustrated that VO x /KIT‐6 and VO x /SBA‐15 had large specific surface areas and good dispersion of vanadium species. The H 2 ‐TPR and XPS results confirmed that VO x /KIT‐6 had stronger reducibility and higher relative content of O ads /(O ads +O latt ) than those of VO x /SBA‐15 and VO x /SiO 2 . The good performance of soot oxidation in the plasma‐catalytic systems over VO x /KIT‐6 could be attributed to 1) the well‐developed 3D mesoporous structure, which facilitated the transportation of radicals and active species, and 2) improved redox properties of VO x /KIT‐6, since more active sites and surface adsorbed oxygen species on the catalyst surfaces could contribute to soot oxidation.