Improved ultraviolet radiation stability of Mn2+-doped CsPbCl3 nanocrystals via B-site Sn doping

Enhancing the highly ultraviolet irradiation stability of luminescent Mn2+-doped all-inorganic halide perovskite nanocrystals (NCs) is challenging because their optical properties depend on their ionic structure and its inherent defects. Herein, we presented a facile and effective synthesis method using a B-site Sn doping strategy to grow Mn2+-doped CsPbCl3 (Mn:CsPbCl3) NCs with enhancement in ultraviolet irradiation stability and emission efficiencies. Mn:CsPbCl3 NCs were prepared by tailoring the amount of SnCl2 added during the growth of NCs. The element and microstructure analysis revealed that the Sn ions were successfully doped into the host NC lattice and had the valence state of +2. With the increase in the Sn doping content, the doping efficiency of the Mn2+ ions increased and the photoluminescence (PL) intensity of NCs was enhanced. The optimum synthesis of Mn:CsPbCl3 NCs was obtained at an Sn/Mn/Pb molar ratio of 1/1/1, and the PL quantum efficiency reached 43%. More importantly, on increasing the ultraviolet illumination time, almost unchanged single exponential decay times of the Mn2+ emissions and slow reduction in the PL intensities of Mn:CsPbCl3 NCs were found after Sn doping, indicating that Sn doping can significantly improve the ultraviolet irradiation stability of Mn:CsPbCl3 NCs.