Selection of Gd2(WO4)3:Tb3+ for inproving color deviation in white light-emitting diodes

Abstract

<span lang="EN-GB">This study successfully using the hydrothermal technique to synthesize <a name="_Hlk81726620"></a>Gd<sub>2</sub>(WO<sub>4</sub>)<sub>3</sub>:Tb<sup>3+</sup> phosphors when subjected to calcination under the temperature of 900°C. Here are some aspects that were thoroughly examined: the crystal formation, photoluminescence, photoluminescence excitation, as well as fluorescent degradation for the samples. The (Gd<sub>2-x</sub>Tb<sub>x</sub>)(WO<sub>4</sub>)<sub>3</sub> (x=0.01-0.15) phosphors exhibit a bright discharge of green under 547 nm (<sup>5</sup>D<sub>4</sub>→<sup>7</sup>F<sub>5</sub> shift for Tb<sup>3+</sup>) when excited at 270 nm (<sup>4</sup>f<sub>8</sub>→<sup>4</sup>f<sub>7</sub><sup>5</sup>d<sub>1</sub> shift for Tb<sup>3+</sup>). Because of the exchange interaction between Tb<sup>3+</sup>, the quenching concentration was determined to be around 10%. The addition of Tb<sup>3+</sup> had no effect on the (Gd<sub>2-x</sub>Tb<sub>x</sub>)(WO<sub>4</sub>)<sub>3</sub> phosphors' CIE chromaticity coordinates (~0.33±0.02, ~0.60±0.02) or color temperatures (~5542 K). Nevertheless, when the Tb<sup>3+</sup> content increased, the fluorescence lifespan for 547 nm emission reduced due to energy transfer between Tb<sup>3+</sup>. The strong green emission from Gd<sub>2</sub>(WO<sub>4</sub>)<sub>3</sub>:Tb<sup>3+ </sup>phosphors is a potential element for WLEDs and display areas.</span>