Highly efficient green-emitting nanocrystals of MAPb1-xMnxBr3 perovskite with excellent thermal stability

Although organic-inorganic hybrid MAPbBr 3 (CH 3 NH 3 +  = MA) perovskite nanocrystals (NCs) have outstanding optical properties , their toxicity and the low thermal stability seriously hinder the further application. Herein, the low-toxic MAPb 1- x Mn x Br 3 NCs were synthesized by the modified ligand-assisted re-precipitation (LARP) approach at room temperature. The mixed-metal NCs exhibit high PLQYs (more than 93%) due to a certain amount of Mn 2+ doping effectively inhibits the non-radiative recombination, and thus improves the optical performance. The as-synthesized perovskite NCs also show excellent thermal stability because of the elimination of structural distortion by Mn 2+ -doping. The fast anion exchange of Mn 2+ -doped perovskite NCs effectively extends their photoluminescence to the whole visible spectral region. Interestingly, a novel dual-emission was observed in MAPb 1- x Mn x (I/Br) 3 ( x  = 0.3) perovskite NCs due to the phase separation.