Multicolor emission from lanthanide ions doped lead-free Cs3Sb2Cl9 perovskite nanocrystals

The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide perovskite materials, although some works have reported the lead-free perovskite nanocrystals (NCs), the photoluminescence quantum yield (PLQY) of these materials is still not unsatisfactory. Meanwhile, because the halogen ions can be easily exchanged, the controllable multicolor emission in perovskite NCs is difficult to realize in current reports. In this work, we introduced lanthanide ions into lead-free Cs3Sb2Cl9 perovskite NCs. Benefitting from the energy transfer between Cs3Sb2Cl9 perovskite NC host and lanthanide ions, the multicolor emission was realized. Based on controlling the doping concentration of Tb3+ and Eu3+ ions, the white light emission under UV excitation would be turned easily in the Tb3+/Eu3+ codoped NCs. In addition, efficient energy transfer from perovskite NCs to Tb3+ or Eu3+ ions is beneficial to improving the optical properties of lead-free perovskite NCs, resulting in maximum PLQYs of red, green and white light emission of 22.6%, 19.7% and 28.5%, respectively. Finally, a white light emitting device (WLED) was fabricated with a power efficiency of 18.5 lm/W, which presents the Commission Internationale de l’Eclairage (CIE) of (0.33, 0.35).