Luminescence Enhancement of CsMnBr3 Nanocrystals through Heterometallic Doping

The absorption and photoluminescence (PL) of CsMnBr3 with Mn(II) in octahedral crystal fields are extremely weak due to a d–d forbidden transition. Herein, we introduce a facile and general synthetic procedure that can prepare undoped and heterometallic doped CsMnBr3 NCs at room temperature. Importantly, both PL and absorption of CsMnBr3 NCs were significantly improved after doping a small amount of Pb2+ (4.9%). The absolute photoluminescence quantum yield (PL QY) of Pb-doped CsMnBr3 NCs is up to 41.5%, 11-fold higher than undoped CsMnBr3 NCs (3.7%). The PL enhancement is attributed to the synergistic effects between [MnBr6]4– units and [PbBr6]4– units. Furthermore, we verified the similar synergistic effects between [MnBr6]4– units and [SbBr6]4– units in Sb-doped CsMnBr3 NCs. Our results highlight the potential of tailoring luminescence properties of manganese halides through heterometallic doping.