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 CrO _x- 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-C _T 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.