Impact of Morphological Effects on the Activity and Stability of Tungsten Carbide Catalysts for Dry Methane Reforming

摘要

Fundamental understanding of the effects of phase and exposed facets of transition metal carbide (TMC) catalysts on reactivity is a route to preparing more active and stable materials for targeted applications. In this work, two geometries of tungsten carbide nanomaterials, nanorods, and nanoparticles with different exposed facets were synthesized to investigate the impact of morphological effects on the catalytic performance for the dry methane reforming (DMR) reaction. beta-W2C nanoparticles maintained high activity and exhibited less coke formation for more than 40,000 turnovers, while alpha-WC nanorods began to deactivate after only 8000 turnovers. The difference in reactivity is attributed to the promotion of coke formation by the exposed facets of the nanorods, while the diverse facets of the nanoparticles inhibit coke formation and promote the DMR reaction. The synthesis of a variety of TMC morphologies provides an avenue for the future study and design of viable catalysts for a wide range of applications.