Synergetic effect between photocatalysis on TiO2 and solar light-driven thermocatalysis on MnOx for benzene purification on MnOx/TiO2 nanocomposites

Abstract

MnO_x/TiO₂ nanocomposites are prepared by the hydrothermal redox reaction of Mn(NO₃)₂ and KMnO₄ with KMnO₄/Mn(NO₃)₂ molar ratio of 2 : 1 in the presence of TiO₂(P25). The MnO_x/TiO₂ nanocomposites are characterized by XRD, TEM, EDX, XPS, and BET. Manganese oxide supported on TiO₂ nanoparticles is amorphous. The MnO_x/TiO₂ nanocomposites can efficiently transform absorbed solar energy into thermal energy, resulting in a considerable increase of temperature. The MnO_x/TiO₂ nanocomposites exhibit excellent catalytic activity and durability for the gas-phase oxidation of carcinogenic and recalcitrant benzene under the irradiation of full solar spectrum light and visible-infrared light. For the first time, we find a synergetic effect between photocatalysis on TiO₂ and solar light-driven thermocatalysis on supported manganese oxide, which significantly improves the catalytic activity of the MnO_x/TiO₂ nanocomposites.