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Near-infrared (NIR) glass-converted light-emitting diodes (gc-LEDs) are newly emergent broadband light sources for miniaturizing optical systems like spectrometers. While lots of effort has been spent on materials doped with rare-earth and transition-metal ions, the achievement of these materials with broadband NIR emission and desired wavelength region remains a long-standing challenge, especially operating in the spectral region between 700 and 1100 nm. Herein, a broadband NIR LEDs based on Te cluster-doped silicate glass is developed. Through adjustment of melting atmosphere and network topology of the glass matrix, active NIR Te cluster centers can be generated and stabilized in silicate glass and show a broad emission at 980 nm with a full width at half maximum (FWHM) of 300 nm under blue light excitation. The photoluminescence of the glass matches well with the absorption of several primary chemical bonds in food and biological tissue. In demonstration experiments, the NIR absorption of different biological tissue by NIR light from our glass is measured, suggesting that the super-broad NIR luminescence of Te-doped silicate glass has potential applications as light sources for nondestructive analysis. [ABSTRACT FROM AUTHOR]

Broadband near-infrared (NIR) spectroscopy based on glass-converted light-emitting diodes (gc-LEDs) has been of great interest to multifunctional applications ranging from night vision to chemical industry, stimulating the demand for exploring broadband NIR gc-LEDs with sufficient efficiency stability and aging resistance. Herein, an all-inorganic broadband NIR LEDs based on Te cluster-doped germanate glass is developed. Via adjustment of melting atmosphere and network topology of the glass matrix, active NIR Te cluster centers can be generated and stabilized in germanate glass and show a broad emission at 770 nm with a full width at half maximum (FWHM) of 260 nm under blue light excitation. By combining the Te-doped glass with a commercial blue LED chip, a high-performance NIR gc-LEDs is fabricated with an NIR output power of 14.21 mW@10.1% under a driving current of 400 mA. Particularly, the fabricated NIR-LED device exhibits high efficient stability with a relatively low-efficiency drop of 0.0023 %mA−1, and excellent aging resistance while retaining an electroluminescence intensity up 90 % of their initial value after aging for 480 h under harsh conditions, which is comparable to the commercial phosphors. Finally, its multifunctional application of gc-LEDs is also demonstrated. [ABSTRACT FROM AUTHOR]