Melt-quench technique;
Glass transition temperature;
Crystallization temperature;
Ceramic;
Optical band gap;
Wide band gap material;
UP-CONVERSION;
LUMINESCENCE PROPERTIES;
IONS;
EMISSION;
SILICA;
IR;
D O I:
10.1016/j.optmat.2015.03.038
中图分类号:
T [工业技术];
学科分类号:
08 ;
摘要:
Eu3+ doped tellurite glass has been synthesized through melt quench method and studied in details at room temperature. The heat treatments to the glass sample convert it into glass-ceramic and ceramic which could be verified structurally by TEM, SEM, XRD measurements. The effect of this on the optical properties of the sample has been studied by UV-Vis-NIR, FTIR, and PL measurements. The optical band gap (E-opt) has been found to increase from 3.82 to 4.04 eV as the sample changes to ceramic from glass. This material thus can also be used as tunable wide band gap (WBG) material whose band gap can be tuned by selective heat treatment of the glass sample. PL measurements show that the emission intensity of Eu3+ decreases as we go from glass to glass-ceramic and then ceramic. The decrease in emission intensity in case of ceramic is well supported by lifetime measurements. The excitation and downconversion (DC) emission mechanism is illustrated by energy level diagram. (C) 2015 Elsevier B.V. All rights reserved.