Broadband near-infrared emission in Cr3+-doped MgO-Al2O3-SiO2 dual-phase glass-ceramics for near-infrared spectroscopy applications

Broad-band and high-efficiency NIR-emitting materials are widely used in near-infrared (NIR) spectroscopy technology. Here, a series of Cr3+-doped dual-phase glass-ceramics were successfully prepared. The Mg2Al4-Si5O18 and MgAl2Si3O10 nanocrystals with particle sizes smaller than 200 nm were precipitated simultaneously in glass-ceramics. The density and molar volume showed an opposite trend with the rise in crystallization temperatures. The two excitation bands were revealed in the excitation spectra monitored at 985 nm, and the crystal field strength of Cr3+ was 2.259 similar to 2.542. Under the excitation of 400 nm and 466 nm xenon lamps, the broadband emission peaks centered at -985 nm with a full width at half maximum of 148-169 nm were observed, indicating that the dual-phase glass-ceramics were suitable for NIR spectroscopy. Furthermore, the tunable emission was achieved by selective enrichment of Cr3+ ions into Mg(2)Al4Si(5)O(18) and MgAl2Si3O10 nanocrystals, which paves the way for the development of high-efficiency and broadband NIR emitting materials.