Applied Catalysis B: Environmental, Vol.240, 141-152, 2019
Noble metal free, CeO2/LaMnO3 hybrid achieving efficient photo-thermal catalytic decomposition of volatile organic compounds under IR light
Large amounts of anthropogenic VOCs emissions give rise to photochemical smog and ground-level ozone. Currently, catalytic oxidation for VOCs elimination still requires energy-intensive high temperatures. Lightdriven photo-thermocatalysis oxidation of VOCs holds great promise to substantially reduce energy consumption for sustainable development in comparison with conventional thermal-based catalytic oxidation. Herein, CeO2/LaMnO3 composite, featuring the broad light wavelength absorption (800 similar to 1800 nm), can be used as a highly active photo-thermal responsive catalyst on VOCs decomposition under IR irradiation. The maximum photothermal conversion efficiency is able to reach 15.2% with a significant toluene conversion of 89% and CO2 yield of 87% under IR irradiation intensity of 280 mW/cm(2), together with excellent stability of nearly 30 h. Comparative characterizations reveal that such photo-thermal catalytic activity enhancement is predominantly attributed to the synergistic effects of ultrabroadband strong light absorption, efficient light-to-heat conversion, good low temperature reducibility and high lattice oxygen mobility, originating from an intense interaction of LaMnO3 with CeO2. Toluene oxidation reaction on CeO2/LaMnO3 catalyst proceeds via a Mars-van Krevelen mechanism as evidenced by in situ diffuse reflectance infrared Fourier transform spectroscopy.