Switching on Near-Infrared Light in Lanthanide-doped CsPbCl3 Perovskite Nanocrystals.pdf

The accessible emission spectral range of lead halide perovskite (LHP) CsPbX3 (X = Cl−, Br−, I−) nanocrystals (NCs) has remained so far limited to wavelengths below 1 μm, corresponding to the emission line of Yb3+, whereas the direct sensitization of other near-infrared (NIR) emitting lanthanide ions is unviable. Herein, we present a general strategy to enable intense NIR emission from Er3+ at ~1.5 μm, Ho3+ at ~1.0 μm and Nd3+ at ~1.06 μm through a Mn2+-mediated energy-transfer pathway. Steady-state and time-resolved photoluminescence studies show that energy-transfer efficiencies of about 39%, 35% and 70% from Mn2+ to Er3+, Ho3+ and Nd3+ are obtained, leading to photoluminescence quantum yields of ~0.8%, ~0.7% and ~3%, respectively. This work provides guidance on constructing energy-transfer pathways in semiconductors and opens new perspectives for the development of lanthanide-functionalized LHPs as promising materials for optoelectronic devices operating in the NIR region.