Structure, luminescent properties and FDTD simulation of TeO2-BaO-Bi2O3-Ag:Ln3+ glass-ceramics system

TeO2-BaO-Bi2O3-Ag glass systems (TBB) co-doped with terbium and europium ions have been successfully synthesized through conventional melt-quenching technique. Heat treatment procedure at 350 °C has been conducted in order to synthesize silver nanoparticles embedded in TBB glass matrix. Structural measurements involved XRD studies that revealed no crystallization of glass structure after heat treatment at elevated temperatures. TEM measurements revealed successful silver nanoparticles synthesis after annealing for 24 h. Mean size of nanoparticles was determined and equaled approximately 50 nm for exemplary heat treated sample. UV-VIS study shown characteristic features of terbium and europium ions as well as LSPR band at approximately 550 nm. Photoluminescence measurements presented the possibility of simultaneous excitation of Eu3+ and Tb3+ with single wavelength. Moreover, possible energy transfer between Tb3+ and Eu3+ is discussed. Lifetimes of europium and terbium excited states have been measured. Shift of the emission colour from red to yellowish white has been observed when europium to terbium ratio was being changed. Thus, synthesized samples exhibited very good colour tunability induced by the change of composition. Also, the finite-difference time domain (FDTD) method has been applied to simulate electromagnetic field propagation through the selected sample.