The growing demand for spectroscopy applications in the areas of agriculture, retail and healthcare has led to extensive research on infrared light sources. The ability of phosphors to absorb blue light from commercial LED and convert the excitation energy into long-wavelength infrared luminescence is crucial for the design of cost-effective and high-performance phosphor-converted infrared LEDs. However, the lack of ideal blue-pumped short-wave infrared (SWIR) phosphors with an emission peak longer than 900 nm greatly limits the development of SWIR LEDs using light converter technology. Here we have developed a series of SWIR-emitting materials with high luminescence efficiency and excellent thermal stability by co-doping Cr3+-Yb3+ ion pairs into Lu0.2Sc0.8BO3 host materials. Benefitting from strong light absorption of Cr3+ in the blue waveband and very efficient Cr3+→Yb3+ energy transfer, the as-synthesized Lu0.2Sc0.8BO3:Cr3+,Yb3+ phosphor emits intense SWIR light in the 900–1200 nm from Yb3+ under excitation with blue light at ~460 nm. The optimized phosphor presents an internal quantum yield of 73.6% and the SWIR luminescence intensity at 100 °C can still keep 88.4% of the starting value at 25 °C. SWIR LED prototype device based on Lu0.2Sc0.8BO3:Cr3+,Yb3+ phosphor exhibits exceptional luminescence performance, delivering SWIR radiant power of 18.4 mW with 9.3% of blue-to-SWIR power conversion efficiency and 5.0% of electricity-to-SWIR light energy conversion efficiency at 120 mA driving current. Moreover, under the illumination of high-power SWIR LED, covert information identification and night vision lighting have been realized, demonstrating a very bright prospect for practical applications.

Short-wave infrared (SWIR) spectroscopy has recently emerged as an important technology across a wide range of areas, whether industrial, biomedical, or environmental. Nevertheless, it is still a longstanding challenge to develop robust SWIR light sources. The SWIR phosphor-convert light emitting diodes (LEDs) by coating blue LED chips with desirable SWIR-emitting phosphors are becoming an ideal alternative for solid-state SWIR light sources due to its compactness, low-cost, and long operating lifetime, as does the commercial white LEDs. Herein, we report a blue-pumped Cr 3+ -doped LiScGeO 4 SWIR phosphor as a luminescent converter for phosphor-convert SWIR LEDs. This phosphor shows an intense SWIR emission band with a peak wavelength at ∼1120 nm owing to the 4 T 2 → 4 A 2 electron transition of Cr 3+ when exciting with blue light. The full width at half-maximum (fwhm) of the phosphor is ∼300 nm and the absolute quantum efficiency is determined to be ∼26%. SWIR LED prototypes are constructed by combining the optimized phosphor materials with commercial blue InGaN LED chips, which can generate a commendable emission band in the SWIR region over 800−1600 nm and achieve a maximum output power of ∼4.78 mW at 60 mA with the photoconversion efficiency of 4.4%. The current exploration of Cr 3+ -doped SWIR-emitting phosphors will lay the foundation to engineer phosphor-convert SWIR LEDs for applications in night-vision surveillance and SWIR spectroscopy technology. These blue-light-excitable SWIR-emitting phosphors can serve as an important complement to the spectral gap of the current Cr 3+ -doped phosphors in the SWIR region and will pave the way toward cost-effective phosphor-converted solid-state SWIR light sources.

Persistent phosphors emitting in the ultraviolet (UV) spectral region have attracted great attention in recent years, owing to their promising implications to many advanced applications ranging from photocatalysis to phototherapy....

Ultraviolet (UV) luminescent materials hold great promise for applications across a wide number of fields, whether environmental, biological or medical. However, luminescent materials with the capability to continue emitting UV...

Inorganic luminescent materials that emit in the ultraviolet-B (UVB) region (280–320 nm) have gained considerable attention in recent years because of the growing demands for photochemistry and photomedicine applications. However,...

Trivalent bismuth (Bi3+) has been regarded as a favorable emitting center since it can give off light of different wavelengths from ultraviolet (UV) to red in different host materials. These...

Blue light‐emitting diode (LED) pumped short‐wave infrared (SWIR; 900–1700 nm) emitters are providing new solutions in the design of portable and cost‐effective infrared light sources for medical, surveillance, and spectroscopy applications by taking advantage of converter technology. However, desirable blue‐light‐excitable SWIR‐emitting phosphors with a peak wavelength longer than 1000 nm are lacking. Herein, a promising broadband SWIR phosphor is designed and developed by incorporating Cr3+‐Ni2+ ion pairs into LiMgPO4 host. Upon 450 nm blue light excitation, the as‐synthesized LiMgPO4:Cr3+,Ni2+ phosphor exhibits a broad and intense SWIR emission spanning from 1100–1600 nm with peak wavelength at 1380 nm and a full width at half maximum of 273 nm due to the efficient energy transfer from Cr3+ to Ni2+. Moreover, phosphor‐converted SWIR LED prototype device based on the combination of 450 nm blue LED chip and the optimized phosphor is fabricated as a new type of broadband illuminator covering the SWIR waveband, delivering a maximum radiant power of ≈2.7 mW at 120 mA driving current. Benefiting from the distinct spectral characteristics of SWIR light, the practical relevance of the fabricated SWIR illuminator is demonstrated in covert information identification and night vision lighting.

Near-infrared (NIR) phosphor-converted light-emitting diodes (LEDs) are becoming an efficient and promising solution for high-power NIR light sources, which have shown a broad range of possible applications in the fields...