Mn Derived Growth of CsPbBr3 Nanoplatelets for Stable and Bright Orange Emission

Mn-doped perovskites have been extensively studied in optics, magnetism, and electronics due to their orange emission. However, successful Mn doping required a high Mn/Pb feed ratio. In this paper, Mn-doped CsPbBr 3 nanoplatelets (NPLs) with bright orange emission were prepared by a two-step slow thermal injection synthesis. The slow injection of precursors effectively slow-down the crystal growth kinetic process and controls the growth of undoped CsPbBr 3 NPLs. This process also significantly improves Mn doping efficiency. Mn doping induced the generation of numerous precursor clusters during the growth of CsPbBr 3 NPLs, and the formation of these clusters was crucial for enhancing the doping efficiency. The maximum amount of Mn precursor in CsPb 0.83 Mn 0.17 Br 3 was 50% of Pb precursors. The photoluminescence quantum yields (PLQYs) of CsPb 0.94 Mn 0.06 Br 3 NPLs reached up to 80.6%, which was 3.1 times of that of CsPbBr 3 NPLs. The PL properties of Mn-doped CsPbBr 3 NPLs were significantly enhanced compared with pure CsPbBr 3 NPLs. The growth process and luminescence mechanism of Mn-doped CsPbBr 3 NPLs were discussed. High PLQYs and efficient Mn doping supplied an ideal approach for the preparation of various CsPbX 3 (X = Cl, Br, and I) NCs for commercial applications.