Studies on tunable emission properties and energy transfer of Sm3+ or Tb3+-sensitized tellurite glasses by Dy3+ co-doping

The spectral interaction and energy transfer (ET) mechanism of Dy3+ ions with co-doped Sm3+ or Tb3+ ions in tellurite glass were systematically explored to enable a good color tunable property and to develop a technique with improved performance for solid-state lighting applications. Comprehensive spectral characterization showed that Dy3+ ions sensitized Sm3+ and Tb3+ ions. Importantly, the ET process was investigated and ET from Dy3+ ions to Sm3+ ions (Dy3+*Sm3+ ET) and reverse ET from Tb3+ to Dy3+ ions (Tb3+*Dy3+ reverse ET) were identified. The ET efficiency of Dy3+ for Sm3+ and Tb3+ ions was 76.98 % and 22.82 %, respectively. The chromaticity coordinates were calculated by the CIE 1931 diagram and then the corresponding correlated color temperatures were calculated. The data indicated that Dy3+ co-doped Sm3+ or Tb3+-sensitized tellurite glass is in possession of promising potential for light convertor materials at visible wavelengths.