Boosting catalytic oxidation of propane over CeO 2-supported Co 3 O 4 catalyst with strong interfacial interaction and electron transfer

Tuning the nanoparticle-support interaction can optimize the catalytic performance of supported metal oxide catalysts for VOCs removal. Herein, a series of Co 3 O 4 /CeO 2 catalysts with different strengths of interfacial interaction and electron transfer were successfully constructed via various modified wetness impregnation procedures. With the introduction of ammonium hydroxide, citric acid or H 2 pretreatment, a stronger interfacial interaction and electron transfer were achieved due to the highly Co 3 O 4 dispersion and CeO 2 surface reconstruction. The modified-synthesis Co 3 O 4 /CeO 2 catalysts, particularly Co 3 O 4 /CeO 2 -CA (citric acid), demonstrated superior catalytic activity (T 90 = 296 degrees C, TOF = 0.337 x 10 _ 3 s _ 1 ) and stability for propane oxidation as compared to typical wetness impregnation Co 3 O 4 /CeO 2 -DI (T 90 = 314 degrees C, TOF = 0.121 x 10 _ 3 s _ 1 ). Through systematic characterizations and DFT calculation, the strong interfacial interaction and abundant reactive oxygen species facilitate the adsorption and activation of C 3 H 8 and O 2 on the catalyst surface, which further promote the intermediates (carbonate/carboxyl species) transformation. These findings highlight interfacial mechanism to catalytic performance optimization of supported metal oxides.