(H2dabco)[Na(BF4)3]: an ABX3-type inorganic–organic hybrid perovskite compound exhibiting dielectric switching above room-temperature

Abstract

The ABX₃-type inorganic–organic hybrid perovskite (H₂dabco)[Na(BF₄)₃] (H₂dabco = 1,4-diazabicyclo[2.2.2]octane cation, 1) undergoes a static-to-dynamic phase transition at 403/386 K (heating/cooling), respectively. Variable-temperature single crystal structure analysis reveals that the H₂dabco cation and/or BF₄⁻ bridging ligand undergo disordering. Dielectric measurements show a typical switchable dielectric transition between high- and low- dielectric states during the phase transition. Notably, the reversibility of dielectric switching properties of 1 was also identified. These excellent switching characteristics of 1 make it a type of switchable dielectric material.