Enhanced luminescence in 1D corrugated lead bromides via reduced flexibility of trivalent cations†

Hybrid metal halides (HMHs) have attracted considerable attention from researchers exploring broadband luminescence materials due to their low cost and excellent photophysical properties. Although lots of structures have been developed by researchers based on monovalent and bivalent cations, the importance of trivalent cations in the design of low-dimensional HMH materials with broadband luminescence has been overlooked. In our study, we obtained two new 1D corrugated structures (MPEA)PbBr₅·H₂O (MPEA is 4-methyl-1-piperazineethanammonium) and (PEA)₂Pb₂Br₁₀·H₂O (PEA is 1-piperazineethanammonium) based on trivalent cations, which can efficiently emit yellow-white light emission with CIE color coordinates of (0.35, 0.42) and (0.42, 0.47) at room temperature with a photoluminescence quantum yield of 0.6% and 10.9%, respectively. Our research underscores the advantages of utilizing low flexible trivalent cations in the development of HMHs with outstanding broadband emission performance and provides novel insight into the design of advanced solid-state luminescent materials.