Novel broadband near-infrared emitting phosphor LiGe2(PO4)3:Cr3+ with tuning and enhancement of NIR emission by codoping Sb5+

• A novel broadband near-infrared LiGe 2 (PO 4 ) 3 :Cr 3+ phosphor was developed. • The tile phosphor possessed an excellent internal quantum efficiency (90%). • A new idea to achieve tunable near-infrared emission was provided. • The emission intensity of tile phosphor increased to 1.5 times by codoping Sb 5+ . A highly efficient novel broadband NIR emission peaking at 814 nm with a large full width at half maximum (FWHM) of 170 nm was realized in novel LiGe 2 (PO 4 ) 3 :Cr 3+ (LGP:Cr 3+ ) with internal quantum efficiency about 90% (IQE). An innovative strategy of Sb 5+ codoped phosphor (LGP:Cr 3+ ,Sb 5+ ) led to the increases in the luminescence intensity and thermal stability. Moreover, tunable NIR emission from 814 to 743 nm was achieved which can be ascribed to the attenuation of electron-phonon coupling with increasing Sb 5+ -concentration. The output powers of phosphor-converted lighting emitting diodes (pc-LEDs) by combining 460 nm chips with LGP:0.01Cr 3+ and LGP:0.05Cr 3+ ,0.05Sb 5+ phosphors reached 34.68 mW @ 300 mA and 40.36 mW @ 250 mA, respectively. Our results prove that the codoped strategy can provides a new idea for research on tunable NIR phosphors.