Chapter 5 - Synthesis and characterization of upconversion-luminescent fluorosilicate glasses and glass ceramics

Abstract

As a new type of compound glass system, fluorosilicate glass and glass ceramics exhibit excellent optical properties in upconversion photoluminescence. The optimization of the fluorosilicate glass materials’ properties with regard to the application envisioned demands an understanding of the key concepts describing their local structures on different wavelength regimes. Because of the inevitable losses and nanocrystalization of fluorosilicate glass during the fabrication process of melting or annealing, the synthesis and elemental analytical characterization present important and critical challenges. In this contribution, we summarize the current state of the literature regarding the structural characterization of these fluorosilicate glasses, current research activities on optical properties of a series of rare earth and transition metal ions doped fluorosilicate glass and glass ceramics containing KZnF3 nanocrystals fabricated in our lab are reviewed. Exemplary examples will be presented for (a) Yb3+-Yb3+ cooperative upconversion in fluorosilicate glass ceramics; (b) Mn2+-Yb3+ codoped glass and glass ceramics; (c) fluorosilicate glass ceramics with high Mn2+ content; and (d) Yb3+-Er3+ codoped fluorosilicate glass with special phase-separate structure. The potential application fields of this glass material system document the utility of correlated spectroscopic studies using the very simple fabrication methods in understanding the ceramic glass structural foundations of photophysical properties.