Quenching-induced surface modulation of perovskite oxides to boost catalytic oxidation activity.

Quenching is a powerful method for modulating surface structures of metal oxide nanocatalysts to achieve high catalytic oxidation activities, but it is still challenging. Herein, a catalyst of ultrafine Co3O4 nanoparticles decorated on Co-doped LaMnO3 (Co3O4/LaCoxMn1-xO3) is synthesized via one-step quenching perovskite-type LaMnO3 nanocatalyst into an aqueous solution of cobalt nitrate, which exhibits significantly improved catalytic performance with toluene (1000 ppm) conversion of 90% at 269 °C under the gas hourly space velocity of 72000 mL g-1 h-1. The high catalytic activity correlates with large surface area, abundant oxygen vacancies and good reducibility. Furthermore, density functional theory calculations disclose that Co doping and interfacial effect of Co3O4/LaCoxMn1-xO3 can achieve lower C-H bond activation energy. These findings provide a unique and effective route towards surface modification of nanocatalysts.