Boosting the Total Oxidation of Toluene by Regulating the Reactivity of Lattice Oxygen Species and the Concentration of Surface Adsorbed Oxygen

Surface absorbed oxygen (Oads) and surface lattice oxygen (Olatt) specie are critical for accelerating oxidative removal of toluene over MnO2-based catalyst. Herein, an excellent CuMnO2 catalyst has been successfully designed and fabricated. Doping Cu2+ with strong Jahn-Taylor effect into the lattice of MnO2 not only weakens the strength of Mn-O bonds but also induces the formation of oxygen defects, which enhances the reactivity of Olatt and promotes the adsorption of gaseous oxygen molecules. As a result, CuMnO2 reaches 50 % and 90 % of toluene conversion at 212 and 241 degrees C respectively, showing obviously better catalytic performance compared to CeMnO2, NiMnO2, CoMnO2 and 6-MnO2. Moreover, CuMnO2 exhibits outstanding stability, good cycling stability and excellent water resistance ability. The in situ DRIFTS demonstrate that ring opening of benzoate and the dehydrogenation of benzaldehyde are key processes that affect the deep oxidation of toluene.