News and Events

Recently, low-dimensional perovskites have attracted increasing attention as a promising candidate for light emission. Compared to the 3D counterparts, the quasi-2D perovskites exhibit improved stability under harsh environmental conditions due to the incorporation of the hydrophobic organic spacers. Among the two types of quasi-2D perovskites, Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) perovskites, DJ perovskites are of more interest due to their higher stability owing to stronger bonding between perovskite slabs. In this work, we investigated lead- and tin-based DJ perovskites for light-emitting applications. Lead-based perovskites commonly exhibit bright emissions with high color purity. Hence, they were investigated to achieve blue perovskite light-emitting diodes (PeLEDs). Sky-blue PeLEDs with improved performance were achieved by optimizing perovskite composition and device architecture. In contrast to lead-based perovskites, tin-based perovskites commonly exhibit broad emission peaks in yellow to orange spectral region. Thus, they are of interest for possible applications as phosphors for white light emission. While tin-based perovskites are highly interesting due to the lower toxicity of tin compared to lead, they have inferior stability compared to their lead counterparts. Thus, we investigated the stability of tin-based DJ perovskites and the effect of exposure to the environment on their light emission. We found that ambient exposure induces the transformation of 2D HDASnBr₄ into 1D HDA₃SnBr₈(H₂O) phase, and the yellow emission originates from the 1D phase.