Blue LED-excitable ultra broadband near-infrared luminescence based on KCdF3:Cr3+/Ni2+ nanocrystals embedded in fluorosilicate glass

The growing demand for broadband near-infrared (NIR) irradiation in security, biomedicine, and food science is driving the development of new NIR light sources. Herein, a series of Cr3+/Ni2+ co-doped transparent glass ceramics containing octahedrally coordinated KCdF3 nanocrystals have been successfully prepared. Under 450 nm blue light excitation, the combination of Cr3+ and Ni2+ results in an ultra-broadband NIR emission band ranging from 700 to 1800 nm. Based on the excitation and emission spectra and the decay lifetime curves, the energy transfer (ET) efficiency from Cr3+ to Ni2+ is confirmed to be 50.2%. A glass ceramic-converted NIR-LED was fabricated by integrating a commercial blue LED chip with a representative Cr3+/Ni2+ co-doped glass ceramic and has demonstrated potential applications in the areas of covert information recognition and night vision illumination. Our investigation provides new insights into the development of ultra-broadband NIR light sources that are both cost-effective and efficient.