Enhanced Thermally Stability and Broadened Emission for Gd <sub>3</sub> Ga <sub>5</sub> O <sub>12</sub> :Cr <sup>3+</sup> Phosphors via Si <sub>3</sub> N <sub>4</sub> Substitution
SunYueZi Chen, Ziwei Lu, Yongfu Liu, Liangliang Zhang, Jiahua Zhang, Jun Jiang
Abstract
Abstract Far‐red (FR) and near‐infrared (NIR) spectroscopy technologies have attracted extensive attention. How to obtain luminescent materials suitable to FR‐NIR phosphor‐converted light‐emitting diodes (pc‐LEDs) is a crucial challenge. Herein, a Si 3 N 4 ‐substitution strategy is employed to regulate the luminescence of Gd 3 Ga 5 O 12 :Cr 3+ (GGG:Cr 3+ ) phosphors. The bandwidth of GGG:Cr 3+ is 95 nm, and then it is broadened to 116 nm due to the Si 3 N 4 ‐substitution. Furthermore, at 423 K the thermal stability is enhanced to 98.7% of that at room temperature, which is higher than the reported 92.7%@423 K for the Si 3 N 4 ‐free sample. The intensity of the optimal specimen is elevated 2.9 times compared with the Si 3 N 4 ‐free sample sintered at the same condition. The FR pc‐LED is manufactured by using the optimized sample, and its FR output power is 47.1 mW with a conversion efficiency of 15.9% driven by 100 mA. This work paves a new way to design high‐performance NIR phosphors.