Near-infrared (NIR) phosphors have received increasing attention for designing novel solid-state light sources with broadband NIR output. In this work, a novel NIR phosphor LiScP 2 O 7 :Cr 3+ (LSP:Cr 3+ ) is developed with the emissions (750−1100 nm) completely in the NIR spectral range. Under 470 nm excitation, LSP:0.06Cr 3+ shows broadband NIR emissions peaking at ∼880 nm, with a full width at half maximum (FWHM) of ∼170 nm and an internal quantum yield (IQY) of ∼38%. Moreover, photoluminescence (PL) improvements of LSP:Cr 3+ phosphors are achieved by Yb 3+ codoping, leading to the broadened FWHM (up to ∼210 nm), increased IQY (η max = ∼74%), and reduced thermal quenching. The energy transformation processes in LSP:Cr 3+ ,Yb 3+ are quantitatively analyzed on the basis of PL lifetime and QY measurements, revealing that the PL improvements by Yb 3+ codoping principally originate from the energy transfer from Cr 3+ to more efficient and thermally stable Yb 3+ emitters. Finally, NIR phosphor-converted light-emitting diodes (pc-LEDs) are fabricated by combining LSP:Cr 3+ ,Yb 3+ phosphors with blue LED chips, giving a maximum NIR output power of ∼36 mW and photoelectric efficiency of ∼12% at 100 mA drive current. The results suggest that the investigated phosphors would be promising luminescent converters for broadband NIR pc-LED applications.

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A new NIR-emitting phosphor ScBO3:Cr3+ was investigated and its great potential for applications in broadband NIR pc-LEDs was demonstrated.

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Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) hold great potential for applications ranging from night vision to non‐destructive detection. However, it remains a long‐standing challenge to develop NIR phosphors simultaneously with longer‐wavelength broadband emissions and higher efficiency. Herein, ultra‐broadband Ga4GeO8:Cr3+ (GGO:Cr3+) phosphors are developed, with the NIR emission covering 700–1300 nm. Furthermore, tunable emission bands peaking from 835 to 980 nm are achieved simply by varying the Cr3+ concentration. Particularly, emission maxima (λmax) of GGO:xCr3+ shift from 850 to 900 nm without intensity loss when increasing x values between 0.02 and 0.10. An internal quantum yield of 60% is achieved for GGO:0.02Cr3+ (λmax ≈ 850 nm, full width at half maximum (FWHM) ≈215 nm). The origin of tunable ultra‐broadband emissions of GGO:Cr3+ is revealed on the basis of structural and time‐resolved spectroscopic analysis. The pc‐LED fabricated by GGO:0.02Cr3+ exhibits a maximum NIR output power of ≈56 mW at 400 mA drive current, and its application in high‐penetration quality analysis of fruits is also demonstrated. The results indicate that GGO:Cr3+ phosphors have high promise for practical applications in NIR pc‐LED devices.