Erbium upconversion luminescence from sol–gel derived multilayer porous inorganic perovskite film

Abstract

Erbium-doped barium titanate (BaTiO3:Er) xerogel film with a thickness of about 500 nm was formed on the porous strontium titanate (SrTiO3) xerogel film on Si substrate after annealing at 800∘C or 900∘C. The elaborated structures show room temperature upconversion luminescence under 980 nm excitation with the photoluminescence (PL) bands at 523, 546, 658, 800 and 830 nm corresponding to 2H11/2 →4I15/2, 4S3/2 →4I15/2, 4F9/2 →4I15/2 and 4I9/2 →4I15/2 transitions of trivalent erbium. Raman and X-ray diffraction (XRD) analysis of BaTiO3:Er\porous SrTiO3\Si structure showed the presence of perovskite phases. Its excellent up-conversion optical performance will greatly broaden its applications in perovskite solar cells and high-end anti-counterfeiting technologies.