Visualization of highly graded oxygen vacancy profiles in lead-zirconate-titanate by spectrally resolved cathodoluminescence spectroscopy

Abstract

The ultraviolet and visible cathodoluminescence (CL) emitted at room temperature from bulk hard lead-zirconate-titanate polycrystalline perovskite has been systematically collected before and after an annealing cycle conducted in a reducing atmosphere. Spectroscopic assessments have been made of the in-depth stoichiometric profile developed upon annealing from the sample surface toward the subsurface. Trapping of electronic charge and local atomic scale distortions in the perovskite oxygen octahedron influences the variation observed in visible CL emission, while lattice distortions upon annealing directly arise from the formation of oxygen vacancies