Efficiently photothermal conversion in a MnO_(x)-based monolithic photothermocatalyst for gaseous formaldehyde elimination

Volatile organic compound(VOC)pollution has a serious impact on human and urgently needs to be controlled through the development of new methods and catalytic materials.Compared with traditional thermal catalytic oxidation,the synergistic photothermocatalysis is regarded as a green and environmen-tally friendly strategy for organic compound pollutant removal,which can promote spontaneous heating of the surface of catalysts to achieve thermal catalytic reaction conditions via harvesting light irradia-tion.In this paper,a monolithic photothermocatalyst was synthesized through coating graphene oxide(GO)and MnOx in turn on a commercially available melamine sponge,where the GO mainly acted as a photothermal conversion layer to heat the catalytically active MnO_(x).This monolithic catalyst presented excellent photo-induced activity for formaldehyde elimination under ambient conditions(∼90%degrada-tion ratio in 20 min for∼160 ppm initial concentration formaldehyde),and meanwhile possessed a high catalytic durability for multiple cycles.The kinetic study demonstrated that this photothermocatalytic process followed a pseudo-second-order kinetics.Finally,we proposed a possible formaldehyde degrada-tion pathway based on in situ DRIFTS examination.