Structural evolution and its influence on luminescence of SiO2–SrF2–ErF3 glass ceramics prepared by sol–gel method

Er3+ doped SrF2–SiO2 transparent glass ceramics were prepared by sol–gel method and heat treatment. The decomposition of Sr2+–CF3COO− and the formation of SrF2 nano-crystals were found to proceed synchronously in the xerogel. After crystallization of the xerogel, SrF2 nano-crystals with 8–10 nm in size distributed homogenously among the glassy matrix, and the microstructure of the glass ceramic was stable under and at the temperature of 800 °C probably due to interfacial interaction between nano-crystals and glassy matrix. When heat-treated at 800 °C, the chemically bonded water in the sample was eliminated, resulting in the appearance of the visible luminescence bands of 2H11/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions.