Halogen regulation of multifunctional hybrid materials with photoluminescence and dielectric response†

Organic–inorganic hybrid switching materials are extensively employed as stimulus-responsive materials in sensors, intelligent switches, optoelectronic devices, etc. However, the design of organic–inorganic hybrid materials (OIHMs) that integrate the dielectric switching response and superior photoluminescence (PL) continues to encounter challenges. Here, we synthesized three zero-dimensional (0D) organic–inorganic hybrid PL compounds using a halogen regulation strategy, (2,5-FBTA)₂MnX₄ (2,5-FBTA = 2,5-difluorobenzyltrimethylammonium, X = Br, Cl, I), which are FBTAM-Br, FBTAM-Cl, and FBTAM-I. With the halogen atom transitioning from I to Br, the phase transition temperature (T_p) gradually increases due to the enhanced intermolecular interaction force, with the T_p of FBTAM-I, FBTAM-Cl, and FBTAM-Br being 419, 425, and 438 K, respectively. In addition, the three compounds show excellent PL properties, and as the halogen atom transitions from I to Br, the PL quantum yields (PLQY) of FBTAM-I, FBTAM-Cl, and FBTAM-Br are 54.59%, 63.81% and 78.98%, respectively. Through a halogen regulation strategy, multifunctional OIHMs with dielectric and PL properties have been successfully synthesized. This not only enhances comprehension of the correlation between structures and properties but also introduces novel and innovative perspectives for the development of multifunctional OIHMs.