Hybrid perovskite shows temperature-dependent photoluminescence and dielectric response triggered by halogen substitution

Materials exhibiting dielectric switching response and photoluminescence (PL) are promising for sensors and information storage. In previous research, we synthesized a series of materials with red or green PL and dielectric switching capabilities by incorporating luminescent metal halides into organic ammonium compounds. However, effective modification to synthesize organic-inorganic hybrid materials with dielectric switching response and orange PL continues to be a challenge in the respective fields. Orange PL materials are valuable for switching and sensors, and most orange light sources are derived from rare earth elements, making them harder to obtain. We have successfully synthesized two organic-inorganic hybrid materials ([CMPD]PbBr₃ (1) and [BMPD]PbBr₃ (2), CMPD = N-ClCH₂-N-methylpiperidine, BMPD = N-BrCH₂-N-methylpiperidine) that exhibit both orange PL and dielectric switching response. When Cl in compound 1 is substituted by Br in compound 2, the phase transition temperature of the compound is elevated by 45 K. These compounds exhibit captivating orange light emission when exposed to ultraviolet lamps. This research provides insights into exploring multifunctional materials with orange PL and dielectric switching response and provides proof for halogen substitution strategies to design materials with higher phase transition temperatures.