Catalytic activity of non-stoichiometric mixed transition metal oxides of praseodymium with cobalt and nickel of Ln2 MO4 type

Non- Stoichiometric mixed transition metal oxides of spinel type were synthesized by solid state reaction technique at 973, 1073, 1173 and 1273K. Characterization of oxide samples was done by XRD and FTIR methods. The surface and catalytic properties of different samples were determined and correlated. Nickel containing oxides were found a bit more catalytically active in comparison to cobalt oxide samples. Presence of oxalate ion in sample enhances surface properties but deactivate catalytic property simultaneously. Transition metal ions i.e. Ni+2, Ni+3, Co+2 and Co+3 were mainly responsible for the activity of mixed oxides where as inner transition metal ion i.e. Pr+3 ion moderates the catalytic activities of the former. (author)