Hollow Hemispherical Carbon Microspheres with Mo2C Nanoparticles Synthesized by Precursor Design: Effective Noble Metal‐Free Catalysts for Dehydrogenation

Abstract

AbstractNoble metal‐based catalysts are currently widely used for the dehydrogenation of hydrocarbons or the production of H2 from hydrocarbons for various applications. However, these catalysts are expensive and hard to scale up. In this work, a facile template‐assisted synthesis of hollow carbon microspheres possessing ultrasmall molybdenum carbide (Mo2C) nanoparticles (NPs) that can efficiently catalyze the dehydrogenation of hydrocarbons is reported. The hollow structures and catalytic activity of the materials can be tuned, or optimized, by controlling the relative amount of Mo species or template used in their precursors. The bowl‐like hemispherical carbons with ≈20 nm thin shells and <5 nm in diameter Mo2C NPs show superior catalytic activity for dehydrogenation of cyclohexane, with a turnover frequency value of 1 × 10−4 s−1 at 305 °C. The catalytic activity of these microspheres for the reaction is 15 times higher than that of the corresponding incomplete hollow spherical carbon microparticles possessing similar sized Mo2C NPs and also better than that of activated carbon‐supported Pt (Pt/AC). Interestingly also, adding a mere 0.1% Pt into the materials leads to several‐fold increase in their catalytic activity and much higher activity than that of Pt/AC.