Near infrared luminescence of Ba2+/Si4+ co-dopedY3Ga5O12: Cr3+ phosphors and their potential applications

摘要: We synthesized a series of garnet-structured Y3-3yGa5(1-x)-3yO12: xCr3+, yBa2+, ySi4+（x = 0.02, y = 0-0.1） (YGO: Cr3+, yBa2+, ySi4+) near-infrared broadband phosphors via coprecipitation method. Characterization results demonstrated that increasing Ba2+- Si4+ doping concentration induced significant particle size growth while maintaining the garnet structure. Under 600 nm excitation, all samples exhibited characteristic Cr3+ 2E→4A2transition emission centered at 748 nm. Notably, Ba2+- Si4+co-doping produced dual effects: (1) remarkable luminescence enhancement with spectral broadening (FWHM increased from 70 nm to 133 nm), and (2) reduced thermal stability (intensity retention at 413 K decreased from 99% to 57%). To optimize performance, we developed a hybrid system combining thermally stable YGO:Cr3+ (x=0.02) with spectrally broadened YGO:Cr3+ (x=0.02,y=0.005), which was subsequently integrated with 620 nm red LED chips to fabricate high-performance NIR-I phosphor-converted LEDs. This work not only reveals the fundamental doping effects in garnet phosphors but also provides a practical design strategy for near-infrared luminescent materials.