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

Abstract

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 Ca_3−xIn_1.93Ge₃O₁₂:0.07Cr³⁺,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.