Investigation of the surface composition of NiOMgO solid solutions by X-ray photoelectron spectroscopy

The surface composition of NiOMgO solid solutions has been investigated by XPS. It has been found that no appreciable deviation from bulk composition is present, or, if present, it goes in the direction of a slight depletion in Ni ²⁺ ions at the surface. The approximations involved and the problems encountered in the determination of the surface composition of air-exposed oxide samples are discussed.