Photothermal catalytic CO2 oxidative dehydrogenation of propane over a dual functional Pt-GaN/SrTiO3 catalyst

Photothermal CO2 oxidative dehydrogenation of propane (CO2-ODHP) is an environmentally friendly and sustainable route for propylene production and CO2 utilization. In the present work, we developed a Pt-GaN/SrTiO3 dual-functional catalyst to facilitate the reaction. The catalyst achieved propylene and CO yields of 1 mmol·gcat-1·h-1 and 1.2 mmol·gcat-1·h-1 under photothermal conditions at 320 °C, surpassing the performance of previously reported catalysts. Additionally, control experiments and in situ DRIFTS analyses corroborated that GaN and Pt were primarily responsible for the activation of C-H and C=O bonds, respectively, and the photothermal route worked via a distinguished intermediate for CO2 activation in contrast to the thermal route. DFT calculations supported the reaction route involving the coupling direct dehydrogenation of propane and reverse water-gas shift reaction. The present work shines a light on the design of photothermal catalysts with dual functions, particularly for the activation of CO2 and light hydrocarbons. Additionally, it proposes a strategy to initiate high-temperature reactions at relatively lower temperatures.