Efficient and Stable Luminescence from Mn2+ in Core and Core-Isocrystalline Shell CsPbCl3 Perovskite Nanocrystals

Abstract

There has been a growing interest in applying CsPbX 3 (X=Cl, Br, I) nanocrystals (NCs) for optoelectronic application. However, research on doping of this new class of promising of NCs with optically active and/or magnetic transition metal ions is still limited. Here we report a facile room temperature method for Mn 2+ doping into CsPbCl 3 NCs. By addition of a small amount of concentrated HCl acid to a clear solution containing Mn 2+ , Cs + and Pb 2+ precursors, Mn 2+ doped CsPbCl 3 NCs with strong orange luminescence of Mn 2+ at ~ 600 nm is obtained. Mn 2+ doped CsPbCl 3 NCs show the characteristic cubic phase structure very similar to the undoped counterpart, indicating that the nucleation and growth mechanism are not significantly modified for the doping concentrations realized (0.1 at.% -2.1 at.%). To enhance the Mn 2+ emission intensity and to improve the stability of the doped NCs, isocrystalline shell 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 growth was applied. Growth of an undoped CsPbCl 3 shell greatly enhanced the emission intensity of Mn 2+ and resulted in lengthening the radiative lifetime of the Mn 2+ emission to 1.4 ms. The core-shell NCs also show superior thermal stability and no thermal degradation up to at least 110 o C which is important in applications.