Ca3Sc2Si3O12: Ce3+, Cr3+, Li+ Phosphor-in-Glass Film for High-power Laser-Driven Near-infrared Lightings

Abstract

Advanced laser-driven near-infrared (NIR) lighting demonstrates the evolution of invisible lighting/imaging technology towards long distance, high brightness and high resolution. In response to the situation of shortage of laser-driven NIR phosphor color converters with desirable properties, herein, we designed and fabricated a Ca3Sc2Si3O12:Ce3+, Cr3+, Li+ phosphor-in-glass film (PiGF) composite, which succeeded in realizing the blue-laser converted NIR optical output to reach 1.697 W. Elaborate experiments were carried out to optimize preparation conditions and sample parameters. Microstructural and spectroscopic studies demonstrate the insignificant interfacial reaction during sintering and thus the retained luminescent performance of NIR phosphor powders. Upon laser driven, the luminescence saturation behaviors were carefully examined under different excitation modes to gain insight into the saturation mechanism. It was found that Ce3+ ions become more susceptible to heat and Cr3+ ions suffer more from the incident high-density blue photons; and correspondingly, thermal quenching/intensity quenching account for Ce3+ is 71%/29% and for Cr3+ is 26%/74% when the luminescence saturation occurs. The demonstration experiment shows a better imaging effect and deeper penetration capability of the fabricated high-power laser-driven NIR illumination source than the conventional NIR LED, revealing its potential application in night vision and non-destructive analysis and identification.