Steam‐induced dimeric CoO _x sites with strong Lewis acid–base pairs for boosting propane dehydrogenation

Abstract

Propane dehydrogenation (PDH) is an on‐purpose route for propylene production. High‐temperature steam is inherent in catalyst regeneration via coke combustion, making it essential to elucidate the steam‐induced active site evolution and its effect on PDH performance. Herein, combined spectroscopic characterizations and metadynamics simulations reveal that controlled steam pre‐treatment transforms isolated framework Co ²⁺ sites into dimeric CoO _x sites, yielding a propylene formation rate about 8 times that of the untreated catalyst. The superior performance of dimeric CoO _x sites is attributed to the enhanced Lewis acidity at the Co ²⁺ centers and increased basicity at nearby oxygen atoms, facilitating propane C–H bond cleavage via a σ‐bond metathesis mechanism. The efficient PDH performance of the dimeric CoO _x structure was conceptually validated through an ion‐exchange procedure from the cobaltosilicate zeolite. This work offers a new strategy for constructing highly active dimeric CoO _x sites for PDH and provides mechanistic insights into the co‐catalyzed PDH reaction.