Luminescence properties and energy transfer of the near-infrared phosphor Ca3In2Ge3O12:Cr3+,Nd3.

The double doping strategy based on energy transfer is an effective way to regulate the NIR spectral distribution. In this work, Ca3In2Ge3O12:xNd3+ (CIG:xNd3+) and Ca3-x In1.93Ge3O12:0.07Cr3+,yNd3+ (CIG:0.07Cr3+,yNd3+) phosphors are successfully prepared via a high-temperature solid-state method. CIG:0.07Cr3+ shows broadband emission centered at 804 nm, which covers most of the excitation peaks of Nd3+ ions. Under excitation at 480 nm, Cr3+ can provide effective energy transfer to Nd3+. In addition, CIG:0.07Cr3+,0.15Nd3+ has good temperature stability, and maintains 68.98% of the room-temperature intensity at 150 °C. The phosphors can convert short-wave photons to long-wave photons and enhance solar cell utilization, demonstrating the potential application of this material in solar spectral conversion technology.