Photo-induced thermal effect on Pt/CeO2 surface for promoting formaldehyde oxidation performance by photothermal catalysis

Abstract

Formaldehyde is a carcinogenic chemical that seriously endangers the health of human body, the elimination of formaldehyde pollutant in enclosed spaces provides safety for breathing. This work studied Pt/CeO2 catalysts for photothermal formaldehyde oxidative elimination. In comparison with photocatalysis and thermocatalysis, the photothermal catalysis is a more promising technique to eliminate formaldehyde from the synergism between active oxygen species including mobile surface lattice oxygen, adsorbed oxygen and superoxide radical, and from the photo-induced thermal effect on catalyst surface when irradiating sunlight. The oxidative abilities of the active oxygen species were promoted by the thermal effect, which consequently leads to the improved formaldehyde conversion in photothermal catalysis. The mobile surface lattice oxygen, adsorbed oxygen and superoxide radical on the Pt/CeO2 catalysts were characterized by H2-TPR, O2-TPD and ESR, the light adsorptions of the catalysts were evaluated by UV–vis and the actual surface temperatures of the catalysts were measured by thermocouple. This work verifies the more powerful photothermal catalysis for formaldehyde oxidation, which could be extended to other reactions for performance enhancements.