Synthesis and characterization studies of γ-Al2O3 -supported, V-Zr mixed oxide catalysts prepared from OV(OEt)3 and Zr(OnBu)4Electronic supplementary information (ESI) available: Additional discussion sections, surface density plots and XPS spectra of TPR studies. See DOI: 10.1039/c2cy20039b

Steam reforming of hydrocarbons is one of the methods widely used to produce clean hydrogen for fuel cells. In previous studies in this group, a nickel-containing, V 2 O x -ZrO 2 co-grafted catalyst on γ-Al 2 O 3 , prepared from a solution of OV(O i Pr) 3 and Zr(O n Bu) 4 (precursor feed of 1 V nm −2 : 4 Zr nm −2 ) was found to generate significant turnover rates in the production of hydrogen from steam-reforming of alkanes and light alcohols. To investigate the influence of change in vanadium precursor ligand and other reaction conditions including time, temperature, concentration of co-grafting solution etc. on the surface optimization of these supported mixed oxides a compositional range of V 2 O x -ZrO 2 samples were synthesized using co-grafting solutions of OV(OEt) 3 and Zr(O n Bu) 4 . Temperature Programmed reduction (TPR) and X-ray Photoelectron Spectroscopy (XPS) studies furnished further insight into the red-ox behavior of the catalysts under steam-reforming conditions. It was observed that a V 5+ /V 4+ red-ox couple was involved in this catalytic process. Zirconium was observed to be present only in the +4 oxidation state irrespective of temperature and other reduction conditions. Based on this premise it was concluded that the refractory nature of the Zr 4+ species on the surface was responsible in preventing the vanadyl groups from sintering at temperatures above 600 °C, thereby stabilizing the red-ox active species during the steam-reforming process. The novelty of this work lies in that, synthesis and characterization studies of γ-Al 2 O 3 -supported, V-Zr mixed oxide catalysts prepared from OV(OEt) 3 and Zr(O n Bu) 4 have never been conducted before.