Reversible high temperature dielectric switching in a 2H-perovskite compound: [Me3NCH2CH3]CdCl3

Abstract

Organic–inorganic hybrid materials with a high-temperature phase transition have been widely applied as a kind of smart material. In this work, a new organic–inorganic 2H-perovskite compound, namely [Me₃NCH₂CH₃]CdCl₃ (1), is reported with a high temperature dielectric transition showing excellent reversibility and sustainability. 1 has an ABX₃ hybrid perovskite structure, where A is a [Me₃NCH₂CH₃]⁺ cation, B is a divalent metal atom, and X is a halogen atom. Differential scanning calorimetry (DSC) and dielectric measurements were applied for further characterization. Variable temperature single-crystal X-ray diffraction revealed that 1 crystallizes in the orthorhombic Pbca space group (No. 61) at 293 K and hexagonal P6₃/mmc space group (No. 194) at 363 K. The structural phase transition is primarily attributed to an ordered–disordered type resulting from the [Me₃NCH₂CH₃]⁺ cations. Organic–inorganic perovskite compounds, as a result of a long exploration history and forward-looking prospects, can deepen research into molecular materials and their physical properties can be effectively optimized in the next-generation of temperature-responsive electrical switches.