Mo–V–O nanocrystals synthesized in the confined space of a mesoporous carbon

[Display omitted] •Synthesis of a nanocrystalline Mo-V oxide catalyst (Nano-MoVO) is demonstrated.•Nano-MoVO possesses a structure resembling orthorhombic MoVO.•Nano-MoVO facilitates ODH of propane and improves selectivity.•Nano-MoVO exhibited >20 % higher selectivity to propene than other MoVO catalysts. Ternary Mo–V oxide nanocrystals (Nano-MoVO) were hydrothermally synthesized in the confined space of a mesoporous carbon template and tested in the oxidative dehydrogenation (ODH) of ethane and propane. The synthesized nanocrystals are approximately 60 nm in length, 20 nm in diameter on average, and possess a structure resembling orthorhombic MoVO (Orth-MoVO) as indicated by spectroscopic and microscopy characterization. The Nano-MoVO catalyst has a 5-fold higher mesopore volume and a 4-fold larger external surface area than an Orth-MoVO synthesized by a conventional method (Orth-MoVO) as characterized through N2 adsorption analysis. Nano-MoVO shows similar activation energy in the ODH of ethane compared with other conventional MoVO catalysts. However, Nano-MoVO exhibits significantly higher propane/ethane activation rate ratio and higher propene selectivity even in the absence of elements such as Te and Nb that suppress overoxidation of propane-derived species to COx. The results suggest the benefits of the nanocrystalline morphology to limit overoxidation.