Growth Of Molecular Ferroelectric Materials And Its Application In PM2.5 Adsorption

Since the discovery of ferroelectrics,ferroelectric materials have been widely used in photovoltaics,optoelectronic devices,sensors,detectors and other fields.In the past,the research on ferroelectrics mainly focused on inorganic ferroelectrics.But the difficulty in growing large single crystals,toxic and polluting,large coercive field,and so on greatly restrict the application of inorganic ferroelectrics.Therefore,in recent years,the research on molecular ferroelectric materials has become one of the main branches of ferroelectric research.Compared with inorganic ferroelectrics,molecular ferroelectrics have the advantages of green synthesis,easy growth of large single crystals,diverse structures,and mechanical flexibility.Due to the excellent properties and performance of molecular ferroelectrics,this article has studied the growth and properties of organic-inorganic hybrid perovskite ferroelectrics,and found interesting properties.In addition,this article also study molecular ferroelectric-diisopropylamine perchlorate(DIPAP)in depth.We synthesized DIPAP heterostructures and applied it in the field of PM2.5 adsorption.This article will be divided into four chapters.The first chapter is the introduction.This part mainly introduces the research background of this article.The second chapter is about experimental principles and equipment.This part mainly introduces the measurement techniques and measurement principles used in this article.Chapter 3 Chapter 4 is the main body of this article.The third chapter is called pyroelectricity and filed induced spin-flop in(4-(Aminomethyl)pyridinium)2MnCl4·2H2O(Compound 1).Large crystals of compound 1 were grown by slow evaporation of solution.The crystal structure was solved to be Pi,which belongs to the centrosymmetric space group.But small pyroelectric current was detected,ad well as a ferroelectric hysteresis loop.The pyroelectric and the ferroelectric properties were attributed to the strain caused by defects.Temperature-dependent magnetic curves and the M-H curve show that 1 is antiferromagnetic ordering below 2.5 K.A filed-induced spin-flop is observed in the antiferromagnetic ordering state.chapter 4 is named photo-induced PM2.5 adsorption in molecular ferroelectric heterostructures.Ferroelectrics are polar materials with large spontaneous polarization.Particulate matter,PM2.5,may be polarized and adsorbed by ferroelectrics due to spontaneous polarization.Micron-sized rods of molecular ferroelectric material diisopropylamine perchlorate(DIPAP)were synthesized by a freeze-drying method to adsorb PM2.5.After low temperature freeze-drying and subsequent high temperature heating,a stable heterojunction DIPAP structure formed with ferroelectric phase and non-switching phase.The special ferroelectric heterostructure in the DIPAP micron rods gave it excellent photo-induced PM2.5 adsorption.The photoelectric effect has an important role in the photo-induced adsorption.This work shows that molecular ferroelectric heterostructure materials have the potential to be used in creating dust-free spaces and simple outdoor particulate matter removal strategies.With the more and more in-depth research on ferroelectric materials,our understanding of ferroelectric materials will be more profound,its application value will also be developed to a greater extent,and ferroelectric materials will better serve human beings.We hope to improve people’s understanding of molecular ferroelectrics through the research in this article,and promote the application of molecular ferroelectrics.