The Coordination Adjustment And The Construction Of High-dimensional Structures In Hybrid Haloplumbates Through Halogen Bonds

Perovskite hybrid lead halide has attracted much attention due to its remarkable potential in the emerging photovoltaic technology field,and its photoelectric conversion efficiency has rapidly increased from 3.8%to 25%in ten years.However,the instability of perovskite type hybrid lead halide to humidity,heat and light has restricted its commercialization process to a great extent.A large number of studies have shown that the hydrogen bonding between anions and cations is one of the internal factors causing the instability of hybrid materials.Halogen bond has similar bonding strength and high directivity to hydrogen bond,and can be used as a potential substitute for hydrogen bond to construct organic-inorganic hybrid lead halide materials.Moreover,the significant hydrophobicity of halogen bond and the charge transfer between donor and acceptor can endow these materials with inherent wet stability and adjustable properties.Based on this,this paper attempts to introduce halogen bond instead of hydrogen bond into hybrid lead halide structure for the first time,and studies the effect of halogen bond on the structure of hybrid lead halide complex.In the first chapter,the research progress of halogen bond and organic-inorganic hybrid halides is introduced respectively,and then the current development,structural characteristics,synthesis strategies and methods of high-dimensional hybrid perovskite structure are introduced.Finally,the significance and research purpose of this paper are put forward.In the second chapter,a series of organic-inorganic lead halide hybrid complexes PyMe-PbI(1),PyMe-PbCl(2),IPyMe-PbCl/PbI(3),IPyMe-PbI(4),IPyMe-PbCl(5),and IPhTMeN-PbBr(6)were successfully prepared by changing the types of halogen ions in inorganic lead halide,using non halogen donor(PyMe+)and halogen donor(IPyMe+)as organic components.In order to explore the influence of halogen bonds on the structure of hybrid lead halide,X-ray single crystal structure analysis,Hirshfeld surface analysis,density functional theory(DFT)and electron density topological analysis based on the theory of atoms in molecules(QTAIM)were used to systematically compare The above 6 structures were compared and studied.The results found that:firstly,for the same organic cation,the change of the halide anion in the lead halide can have a great impact on the coordination configuration of Pb2+,secondly,for the same inorganic lead halide anion,there are two differences between the presence of halogen bonds and the absence of halogen bonds.This situation shows that the coordination mode of Pb2+ will further change significantly.This result is supported by both experiment and theory.The halogen bond-containing hybrid composites prepared in the previous chapter are all one-dimensional structures.In order to explore whether these halogen bond-containing donor organic components can be used to construct high-dimensional organic-inorganic lead halide hybrid composites,the third paper Chapter Through systematic screening and analysis of conditions,two-dimensional hybrid structures BrPhEtNH3-PbI(10),ClPHEtNH3-PbI(11),IPyMe-PbI₂D and IPyMe-PbI₃D,three-dimensional hybrids were synthesized using organic halogen bond donor cations XPhEtNH3+and IPyMe+Structure,summarized the strategy of preparing high-dimensional hybrid lead halide structure.Finally,this paper is summarized,and the innovation of the paper is refined,and the use of halogen bond design to synthesize organic-inorganic lead halide hybrid composites of different dimensions is prospected.