Electron-driven self-recovery of PtGa bimetallic sub-nanoclusters for enhanced propane dehydrogenation stability

Abstract

Supported PtM bimetallic cluster catalysts exhibit excellent activity in propane dehydrogenation (PDH), owing to the synergistic effects of metal species. However, suppressing the poisonous inactivation of the active sites in harsh environments while preserving their robust activity remains a challenge. In this study, we propose a strategy to mitigate the active sites deactivation and enhance PtGa sub-nanocluster stability via promoting the desorption of coke precursors. As a result, the sub-nanometer PtGa cluster catalyst dispersed by Ga (III) Lewis sites exhibits outstanding specific activity and deactivation constant (k_d). The kinetic and in situ DRIFTS characterizations suggest that the competitive adsorption of H₂ and C₃H₈ on the Pt–Ga^δ+ site at the Pt–GaAlO_x interface optimizes the C–H bond activation. The electron-rich Pt facilitates the migratory behaviors of C₁, C₂, and hydrogen species through electron-transfer effects from partially reduced GaO_x species, thereby facilitating the timely recovery of active sites and contributing to the stability of propane dehydrogenation.