Cr3+and Ni2+Co-doped near-infrared dual-emission garnet phosphor for spectroscopic applications

Near infrared spectroscopy is a simple, fast, and non-invasive technique for detecting the composition of substances. However, most NIR phosphors cannot cover the near-infrared I and II regions, which limits the types of substances that can be detected. Herein, Cr3+, 3 + , Ni2+ 2 + co-activated NIR Y3Al2Ga3O12(YAGG) 3 Al 2 Ga 3 O 12 (YAGG) garnet phosphors were synthesized via high-temperature solid-phase method. Due to the energy transfer from Cr3+ 3 + to Ni2+, 2 + , the emission spectra of YAGG: Cr3+, 3 + , Ni2+ 2 + are composed of NIR I emission of Cr3+ 3 + at 710 nm and NIR II emission of Ni2+ 2 + at 1420 nm. The measured internal and external quantum efficiencies of YAGG: 0.08Cr3+, 3 + , 0.005Ni2+ 2 + under 450 nm excitation are 54.4 %, and 26.7 %, respectively. This sample was selected to fabricate pc-LEDs, and fill the emission spectrum gap with Mg2GeO4: 2 GeO 4 : 0.01Cr3+. 3 + . The pc-LED fabricated with PiG film do not exhibit strong characteristic absorption in NIR II region, significantly reduce the re-absorption and thermal quenching of the phosphors. The electro-optical conversion efficiency of PiG pc-LED reaches 6.49% at 10 mA; The results indicate that YAGG: Cr3+, 3 + , Ni2+ 2 + and the fabricated NIR pc-LED are good near-infrared substance detection light source scheme.