X-ray photoelectron spectroscopy study of LaFeO₃ powders synthesized by solution combustion

LaFeO₃ powders were synthesized using a method involving solution combustion, and the surface properties of these powders were examined by x-ray photoelectron spectroscopy. As the amount of fuel increased during the synthesis, the LaFeO₃ powders became amorphous with a large plate-like shape. It was found that the O 1s spectra were composed of two types of photoelectrons by deconvolutioning the spectra. Photoelectrons with higher binding energy come from adsorbed oxygen (O^-) whereas those with lower energy come from lattice oxygen (O^2-). The ratio of adsorbed and lattice oxygen increased as the ratio of the fuel and nitrate (Φ) increased. The binding energy of both types of oxygen increased as Φ increased due to the formation of carbonates.