Enhanced light-driven photothermocatalytic activity on selectively dissolved LaTi_1-xMn_xO_3+δ perovskites by...

LaTi_1-xMn_xO_3+δ (x = 0.2 and 0.4) perovskite-type catalysts are synthesized by acrylamide polymerization route and etched with diluted HNO₃ for oxidation of toluene as one of typical volatile organic compounds (VOCs). The substitution of Mn cations improves catalytic activity (toluene conversion increased from 0 to 50.6% by substituting 40% of Ti cations with Mn cations) by improving abilities of light absorption and light-to-heat conversion, and acid etching further promotes catalytic activity (toluene conversion increased from 50.6%-95.6% for LaTi_0.6Mn_0.4O_3+δ) by enlarging specific surface area, generating more surface active oxygen, strengthening mobility of surface oxygen, and improving low-temperature reducibility. To explore the origin of the light-driven photothermocatalytic activity of A-LaTi_0.6Mn_0.4O_3+δ by EPR analysis, O₂ desorption and H₂ consumption, we find that the light is not only as a thermal source to provide energy for toluene oxidation but also can promote oxidation reaction by photoactivation.