Regulating the C-H Bond Activation Pathway over ZrO₂ via Doping Engineering for Propane Dehydrogenation

The efficient activation of the C-H bond in light alkanes and their catalyst design are significant for alkane-related catalytic processes in view of theoretical and practical aspects. Here, we report the C-H bond activation mechanism and structure-reactivity relationships of Ga-doped ZrO₂ catalysts in propane dehydrogenation. Experimental and theoretical calculation results suggest that the introduction of Ga into the framework of ZrO₂ alters the C-H bond activation pathway from a stepwise mechanism to a concerted mechanism involving simultaneous cleavage of two C-H bonds in propane, leading to a superior C-H bond activation ability and a lower reaction barrier than state-of-the-art metal oxide catalysts. In addition, a volcano-type dependence of the rate of propene formation on the Ga/Zr ratio is established due to a compromise of intrinsic activity and active site concentration. The strategy of metal incorporation into bulk metal oxide may provide an alternative solution to control the C-H bond activation pathway for efficient propene production.