Infrared-to-visible upconversion enhanced photothermal catalytic degradation of toluene over Yb3+, Er3+: CeO2/attapulgite nanocomposite: Effect of rare earth doping

Developing low cost and efficient strategy to eliminate volatile organic compounds (VOCs) are quite urgent and challenging. Herein, CeO 2 nanoparticles co-doped with Yb 3+ and Er 3+ were immobilized on attapulgite clay (ATP) for photothermal catalytic oxidation of toluene. The CeO 2 :Yb 3+ , Er 3+ /ATP exhibited outstanding catalytic activity with low T 90 of 295 °C (temperature at 90% degradation), satisfactory stability and highly water resistance. The enhanced photothermal catalytic performance can be attributed to the optimal introduction of Yb 3+ and Er 3+ , which promoted the up-conversion of near-infrared light (NIR) to visible light increasing the light utilization. The defects caused by Yb 3+ /Er 3+ doping facilitated the adsorption of O 2 , while the active oxygen species generated from the defects and the photoinduced reactive species not only favored the oxidation of toluene in photothermal catalytic process, but also accelerated the reoxidation of reduced catalyst. Notably ATP support provided large specific surface area and abundant adsorption sites for toluene molecules to promote the deep oxidation and hindered the deactivation of catalysts caused by the accumulation of intermediates. In-situ DRIFTS test revealed that the alkoxide and benzoate appeared as the main intermediates, which can be deeply oxidized under light irradiation. Current work provides a new alternative for photothermal catalytic degradation of VOCs.