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

Abstract

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.

Energy vs Charge Transfer in Manganese-Doped Lead Halide Perovskites

“…Sun et al confirmed the presence of an activation barrier for Mn 2+ luminescence, though these authors found a smaller barrier of ∼0.1 eV . A similar effect was also detected by Zeng et al, with Mn 2+ luminescence quantum yield decreasing with temperature …”

“… 29 A similar effect was also detected by Zeng et al, with Mn 2+ luminescence quantum yield decreasing with temperature. 46 …”

“…29 A similar effect was also detected by Zeng et al, with Mn 2+ luminescence quantum yield decreasing with temperature. 46 Despite available information, the nature of the mechanism responsible for the possible sensitization of the excited manganese 4 T 1 state remains elusive. Temperature-dependent Raman spectroscopy performed by Pradeep et al on Mn:CsPb(Cl/Br) 3 shows a progressive sharpening of the 132 cm −1 Pb−Br stretching phonon mode with increasing temperature, which is strongly coupled to Mn dopant modes.…”

Cyan Emission in Two-Dimensional Colloidal Cs2CdCl4:Sb3+ Ruddlesden–Popper Phase Nanoplatelets

“…Recently, we showed that the introduction in the CsPbBr 3 of a trivalent lanthanide induced the filling of halides vacancies rather than Cs + expulsion. 40 In point of fact, it is known as metal halides are often anions deficient, i.e., present several vacancies in the halide sites. 38 Thus, the Cd 2+ → Sb 3+ is balanced by filling of a Cl − defect.…”