Two-Dimensional Quantum-Confined CsPbBr₃ in Silicene for LED Applications

Perovskites with reduced dimensions are very attractive for LED applications due to their improved stability and efficient energy transfer. This is exemplified by 2D perovskites reported in the literature, predominantly either Dion-Jacobson or Ruddlesden–Popper systems, which typically use long chain alkyl moieties as spacers in order to form 2D layers. Here, we report an approach which uses an inorganic 2D material─silicene─as a template to form two-dimensional quantum-confined CsPbBr 3 (qc-CsPbBr 3 ) layers of less than 5 nm in thickness. This approach can be further generalized to synthesize other types of perovskites with reduced dimensionality. The structural and optical properties of the qc-CsPbBr 3 layers inside silicene were characterized. The qc-CsPbBr 3 -based LEDs demonstrate improved stability under ambient conditions, along with a current efficiency of 13.7 Cd A –1 and external quantum efficiency of 8.5%.