High-performance Gd3Al4GaO12:Cr3+phosphors for next-generation far-red LEDs

Far-red (FR) photosensitive pigment (PFR) is important for plant photomorphogenesis. Phosphor-converted (pc) LED is the next-generation FR light device. How to obtain FR-emitting phosphors with a good external quantum efficiency (EQE), suitable photoluminescence and high thermal stability is still a challenge. Herein, by optimizing the sintering technology and chemical design, we develop an excellent FR phosphor, Gd3Al4GaO12:Cr3+. The phosphor has an emission peak at 734 nm and a band width of 70 nm, matched well with the PFR absorption band. By adjusting the flux of H3BO3 and Cr3+ concentration, the EQE reaches 47.2%, and the thermal stability maintains 96.8% at 423 K. Because of its excellent optical properties, the power-conversion efficiency of the FR pc-LED reaches 24.0% driven at 100 mA, demonstrating the high performance and promising applications in the next-generation FR light source.

Automated summary

An excellent FR phosphor, Gd3Al4GaO12:Cr3+, with good external quantum efficiency (EQE), suitable photoluminescence, and high thermal stability is developed by optimizing the sintering technology and chemical design. The phosphor has an emission peak at 734 nm and a band width of 70 nm, matching well with the PFR absorption band. By adjusting the flux of H3BO3 and Cr3+ concentration, the EQE reaches 47.2%, and the thermal stability remains at 96.8% at 423 K. The power-conversion efficiency of the FR pc-LED reaches 24.0% driven at 100 mA, demonstrating its high performance and promising applications in the next-generation FR light source.