The Design And Dielectric Phase Transition Properties Of Novel Crystalline Materials Containing Sulfur Nitrogen Heterocycle

Materials are widely used in switches,actuators,sensors and varactors because their dielectric constants can be switched between low and high dielectric states under temperature stimulation.Constructing organic-inorganic hybrid materials is an effective way to develop such dielectric switching materials.These materials combine the advantages of organic cations,which can provide the random motion of molecular dipoles,and inorganic anions,which are the sources of semiconductor and magnetic properties as crystal frameworks.In addition,by introducing functional groups into cations,these switching materials can be endowed with new functions.For example,the introduction of thioether groups into cations can give the switchable dielectric material the ability to adsorb the heavy metal Pd,and the material also allows for the detection of its adsorption properties by dielectric measurement.In order to find the materials combining adsorption function and dielectric switching properties,we successfully synthesized eight organic-inorganic hybrid materials by hybridizing thiazolidine or its derivative 2,2-dimethyltetrahydrothiazole with a series of inorganic metal halides:[（CH₂）₃NH₂S]₂[Bi Cl₅]（1）,[（CH₂）₃NH₂S]₂[Zn Br₄]（2）,[（CH₂）₃NH₂S][Bi Br₄]（3）,[C₅H₁₂NS]₂[Bi Br₅]（4）,[C₅H₁₂NS]₂[Bi₂Cl₈]（5）,[C₅H₁₂NS]₂[Sb Br₅]（6）,[C₅H₁₂NS][Sb Cl₄]（7）,[C₅H₁₂NS]₂[Cd Cl₄]（8）.This paper mainly describes the dielectric properties,phase transition behavior,adsorption performance and other physical properties of the materials,and verifies that the dielectric measurement of the switch material can detect whether it has adsorption performance.It is found that materials 1,2,3 and 4 all have the properties of switchable dielectric,phase transition and palladium adsorption properties,and the dielectric switch properties of materials 1,2,3 and4 disappear after palladium adsorption,indicating that the adsorption properties of phase transition materials can be detected by dielectric measurement.The above research provides a new way for the design of novel multifunctional dielectric switch materials.