Air stable and highly efficient Bi(3+)-doped Cs(2)SnCl(6) for blue light-emitting diodes

Cs(2)SnCl(6) perovskite has recently attracted attention as a promising optoelectronic material owing to its better stability and reduced toxicity than its lead counterparts. However, its luminescence performance hardly satisfies the requirements. Hence, a series of Bi(3+)-doped Cs(2)SnCl(6) (Cs(2)SnCl(6):Bi(3+)) with enhanced luminescence were synthesized by a solution-phase route. The results show that the initial concentration of Sn(2+) can adjust the nucleation density and the quality of the crystal nucleus growth, which will affect the Bi(3+) doping amount, crystal morphology, and photophysical properties of Cs(2)SnCl(6):Bi(3+). Cs(2)SnCl(6):Bi(3+) shows excellent stability in the atmosphere with a photoluminescence (PL) of around 456 nm and a photoluminescence quantum yield (PLQY) of 31%. The luminescence performance results from [Bi(Sn(4+))(3+) + V(Cl)] defects caused by the Bi(3+) doping. The blue LED based on the Cs(2)SnCl(6):Bi(3+) phosphor exhibits a long life of about 120 h and a Commission Internationale de L'Eclairage (CIE) color coordinates of (0.14, 0.11). This work demonstrates a strategy for Bi-doped perovskites with good stability. This investigation will facilitate the development of Cs(2)SnCl(6):Bi(3+) for blue LED applications.