Cr3+‐Yb3+‐Ni2+ Tri‐Doped NIR Phosphors with Spectral Output Covering NIR‐I and NIR‐II Regions

Abstract To realize efficient and broadband near infrared (NIR) light in both NIR‐I and NIR‐II regions, Gd 3 Mg 0.5 Al 1.5 Ga 2.5 Ge 0.5 O 12 (GMAGG): Cr 3+ , Yb 3+ , Ni 2+ phosphors are prepared in this study. The effects of Cr 3+ ‐Yb 3+ co‐doping and Cr 3+ ‐Yb 3+ ‐Ni 2+ tri‐doping on the luminescence properties are investigated. GMAGG: Cr 3+ , Yb 3+ exhibits high internal quantum efficiency (IQE) of 96.4%, and near‐zero thermal quenching (96.5%@423 K) in 650–1100 nm. By constructing energy transfer from Cr 3+ to Ni 2+ , the emission range of GMAGG: Cr 3+ , Yb 3+ , Ni 2+ is further extended to 650–1700 nm with a high IQE of 28% and good thermal stability (66%@423 K). The NIR LEDs prepared with GMAGG: 0.04Cr 3+ , 0.008Yb 3+ , and GMAGG: 0.04Cr 3+ , 0.008Yb 3+ , 0.04Ni 2+ exhibit 57.5 and 8.1 mW at an input current of 100 mA, respectively. The results show that GMAGG: Cr 3+ , Yb 3+ , Ni 2+ is a promising NIR phosphor for NIR light sources.