Hybrid Mo–C_T Nanowires as Highly Efficient Catalysts for Direct Dehydrogenation of Isobutane

Direct dehydrogenation of isobutane to isobutene has drawn extensive attention for synthesizing various chemicals. The Mo-based catalysts hold promise as an alternative to the toxic CrOx- and scarce Pt-based catalysts. However, the low activity and rapid deactivation of the Mo-based catalysts greatly hinder their practical applications. Herein, we demonstrate a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts based on Mo–CT hybrid nanowires calcined at different temperatures. In particular, the optimal Mo–C700 catalyst exhibits isobutane consumption rate of 3.9 mmol g–1 h–1 and isobutene selectivity of 73% with production rate of 2.8 mmol g–1 h–1. The catalyst maintained 90% of its initial activity after 50 h of reaction. Extensive characterizations reveal that such prominent performance is well correlated with the adsorption abilities of isobutane and isobutene and the formation of η-MoC species. In contrast, the generation of β-Mo2C crystalline phase during long-term reaction causes minor decline in activity. Compared to MoO2 and β-Mo2C, η-MoC plays a role more likely in suppressing the cracking reaction. This work demonstrates a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts.