Dy3+/Cr4+ doped CaLuGaO4 phosphors emitting white and broad NIR light

A phosphor that emits both white light and broad near-infrared (NIR) light is of significant interest across various fields, as it enables both visual inspection and NIR spectroscopic detection. In this study, we designed Dy 3+ /Cr 4+ codoped CaLuGaO 4 phosphors that emit both white light and broad NIR light ranging from 1100 nm to 1700 nm when excited at 450 nm. The white light is produced by the 4 F 9/2  →  6 H 15/2 , 6 H 13/2 , 6 H 11/2 transitions of Dy 3+ . The broad NIR light arises from the 3 T 2 to 3 A 2 transition of Cr 4+ . Additionally, energy transfer from Dy 3+ to Cr 4+ occurs in the Dy 3+ /Cr 4+ codoped CaLuGaO 4 phosphors, allowing for tunable ratios of white light to NIR light by varying the concentrations of Dy 3+ and Cr 4+ . A phosphor-converted light-emitting-diode was constructed by encapsulating the synthesized phosphors around a commercial blue LED chip, demonstrating potential applications in lighting sources and non-destructive spectral analysis.