The Fabrication And Circularly Polarized Luminescence Of Chiral Supramolecular Polymer

Chirality is ubiquitous in nature,which is of great significance in life processes and biological systems.Recently,circularly polarized luminescence(CPL)materials with chiroptical properties have aroused increasing attention due to their widely potential application in 3D display,information storage and anti-counterfeiting encryption.In order to promote the application of CPL-active material,the key issue is to achieve a large luminescence dissymmetry factor(g_lum).Chiral supramolecular polymers driven by non-covalent interactions can effectively improve the CPL of chiral luminescent materials.However,it is difficult to analyze the structure of supramolecular polymers driven by conventional non-covalent interactions owing to their low degree of order.Hence,two crystalline chiral supramolecular polymers driven by halogen bond and coordination are fabricated in this paper,and the morphology,photophysical properties,chiral optical properties and the structure of the chiral supramolecular polymers are characterized.The main research contents are as follows:Two bis-pyridyl-based binaphthalene derivatives R/S-BPy and R/S-BAPy were designed and synthesized working as the halogen bond acceptor,which further co-assembled with the halogen bond donor 1,4-Diiodotetrafluorobenzene to form two kind of chiral supramolecular polymers.The chiral supramolecular polymers formed by R/S-BPy(or BAPy)with F₄DIB displayed chiral fractal structure,and the chirality of the fractal structure is the same as the absolute configuration of R/S-BPy(or R/S-BAPy).Meanwhile,enhanced circularly polarized luminescence can be observed in these two kinds of chiral supramolecular polymer compared with the monomer.The study result shows that BPy(or BAPy)and F₄DIB are brought together to form a chiral supramolecular chian driven by halogen bond,then formed the chiral fractal structure with the help of hydrogen bond or?-?interaction.R/S-BPy/F₄DIB(or R/S-BAPy/F₄DIB)self-assembled systems realized hierarchical chiral transfer from R/S-BPy(or R/S-BPy)molecule to chiral fractal structure with interesting chiral fractal structure.Accompanying with the chiral transfer process,an amplified circularly polarized emission is observed in the supramolecular polymer system.A chiral supramolecular polymer fabricated based on halogen bond realized the promotion of circularly polarized luminescence performance,which can provide a new method for fabricating novel functional CPL materials.A bipyridyl-based chiral molecule salen and a dicarboxyl-based 9,10-diethynylphenylanthracene derivative BPEAH were synthesized.These two molecules are used as ligands to co-coordinate with zinc ions by solvothermal method to generate chiral supramolecular coordination polymers.In the process of orderly connecting the salen ligand and BPEAH ligand with zinc ions to form a supramolecular polymer,the salen ligand induces the entire supramolecular polymer to exhibit chirality,and realizes the circularly polarized luminescence in this supramolecular polymer.The study found that the luminescence of BPEAH molecule is quenched in the solid state,after forming a chiral supramolecular polymer with salen ligand the luminescence of BPEAH is enhanced,which improved the performance of circularly polarized luminescence.