A Semiconducting Organic‐Inorganic Hybrid Metal Halide [(C6H15ClNO)2CdBr4] with Switchable Dielectric and Large Phase Transition Thermal Hysteresis.

A semiconducting organic‐inorganic hybrid compound [(C6H15ClNO)2CdBr4] (1), which displays excellent switchable dielectric, has been successfully synthesized. Systematic characterizations including variable‐temperature structural analyses, DSC, TG, variable‐temperature dielectric measurements, solid‐state UV/Vis diffuse reflectance and photoluminescence were performed. DSC curve shows a couple of reversible heat anomaly peaks at 363/322 K on the heating/cooling process with a very large thermal hysteresis of ∼41 K, indicating the first‐order type of phase transition. Obvious dielectric switching occurs at about 364 K and 314 K also with a large thermal hysteresis of ∼50 K in the heating and cooling process, respectively. The large phase transition thermal hysteresis makes 1 a potential latent heat based thermal energy storage materials which can maintain the system over a wide temperature range. Variable‐temperature structural analyses show that the rotating or orientating movement of anion clusters is the mainly attribution for the phase transition of 1. A semiconducting organic‐inorganic hybrid metal halide [(C6H15ClNO)2CdBr4] exhibits switchable dielectric and a large phase transition thermal hysteresis of ∼50 K due to temperature‐triggered rotating or orientating movement of anion clusters. [ABSTRACT FROM AUTHOR]