Experimental and Theoretical Insights into the Potential of V2O3Surface Coatings for Hydrogen Permeable Vanadium Membranes

A grand challenge of vanadium-based H2permeable membranes is the development of effective, cheap, and stable catalysts to facilitate H2dissociation and recombination. This work investigates a facile air treatment to form catalytically active vanadium oxide on the surfaces of dense vanadium foils. The treatment consisted of short air exposure followed by H2reduction at 823 K, which produced a well-faceted and nanocrystalline V2O3layer on the foil surfaces. The resulting membranes displayed a stable H2permeability of 2 ± 0.25 × 10–8mol·m–1·s–1·Pa–0.5, but transient declines in permeation were observed when operated at both elevated and reduced temperatures. DFT calculations revealed that V2O3(0001) surfaces display barriers and adsorption energies for H2dissociation/recombination that are comparable to those of known H2activation catalysts. It was found that H2dissociation is expected to proceed spontaneously on metal-terminated V2O3, with recombinative-desorption anticipated as the rate limiting step.