Synthesis and characterization of LaCr1-xNixO3 perovskite oxide catalysts

A series of perovskite oxide catalysts with the composition LaCr1-xNixO3 (0 less than or equal to x less than or equal to 1) has been synthesized by a modification of the Pechini method. The oxides have been characterized by powder X-ray diffraction, elemental analysis and surface area measurements. The LaCr1-xNixO3 phases have the orthorhombic GdFeO3 (x < similar to 0.6) and the rhombohedral LaAlO3 structure (x > 0.6), in agreement with previous results. The surface and bulk compositions were shown to be equivalent by XPS measurements. Systematic changes in the binding energies of the Cr 2p and Ni 3p features are indicative of a progressive evolution of the electronic properties with nickel atom content (x). The LaCr1-xNixO3 oxides with x less than or equal to 0.5 were shown by thermogravimetric analysis to be stable at 900 degrees C in H-2/H2O with respect to reduction to nickel metal. (C) 1997 Academic Press.