Enhancement of the NIR Emission of Cr 3+ -Yb 3+ Co-doped La 3 GaGe 5 O 16 Phosphors by Doping Nd 3+ Ions via Efficient Energy Transfer for NIR Spectroscopy Regulation.

The efficient energy transfer in La 3 GaGe 5 O 16 :Cr 3+ , Yb 3+ /Nd 3+ and La 3 GaGe 5 O 16 :Cr 3+ , Yb 3+ , Nd 3+ was investigated in detail. In this phosphor, Cr 3+ acts as the energy absorber (250-700 nm) to sensitize Yb 3+ /Nd 3+ in La 3 GaGe 5 O 16 . Under excitation at 418 nm, La 3 GaGe 5 O 16 :Cr 3+ , Yb 3+ phosphors exhibited a broad emission band in the near-infrared (NIR) region located at 976 nm (La 3 GaGe 5 O 16 :Cr 3+ , Nd 3+ at 1056 nm), which was attributed to the 2 F 5/2 - 2 F 7/2 transition of the Yb 3+ ions ( 2 F 3/2 → 4 I 11/2 transition of Nd 3+ ). Moreover, a Nd 3+ ion was introduced into La 3 GaGe 5 O 16 :Cr 3+ , Yb 3+ . The analysis of excitation spectra and decay time proves that Nd 3+ acts as a bridging ion in the system. This can be used as a new strategy to enhance the energy transfer in Cr 3+ , Yb 3+ co-doped phosphors, and these phosphors have potential applications in NIR spectroscopy regulation.