The Preparation And Properties Of Crystalline Luminescent Materials Based On D-A System

Due to its diversity and excellent structural functions,crystalline materials have shown great application prospects in the field of functional materials and have received extensive attention.At present,the application of crystalline materials mainly focuses on the fields of catalysis,gas storage and separation,sensing,drug delivery and release,etc.However,the preparation and research of crystalline materials with thermal activation delayed fluorescence(TADF)based on donor-receptor(D-A)structural features are less,and studying crystalline materials with TADF function is very important for expanding the research field of TADF materials.In this paper,two kinds of crystalline materials based on D-A architecture features are designed and synthesized.Among them,we synthesized a novel D-A system organic ligand,and prepared a coordination polymer CP1 with TADF properties by self-assembly strategy.We have determined its photocatalytic ability to produce singlet oxygen.In addition,two kinds of covalent organic frameworks(COFs)were prepared,and their fluorescence emission enhancement was enhanced by spatial regulation.Ⅰ.We designed and synthesized a novel crystalline material CP1 with TADF properties.The coordination polymer CP1 is constructed from an organic ligand L with a twisted structure of D-A architecture features.Because it effectively separates the spatial arrangement of the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO),it can decrease the energy difference between lowest excited triplet state and lowest excited singlet state,abbreviated as ?EST.The experimental data shows that both the ligand L and the coordination polymer CP1 have thermal activation delayed fluorescence properties,which expands the research field of TADF materials.The coordination polymer CP1 has the ability to photocatalyze the production of singlet oxygen under illumination conditions.Ⅱ.Design and synthesis of a novel organic compound L-CHO,and applied it to the process of constructing COFs material with D-A structure characteristics.The crystalline material COF-HMAT and comparative material COF-TPA were prepared.Compared with COF-TPA synthesized with tris-(4-formylphenyl)-amine as a monomer,COF-HMAT synthesized with L-CHO as a monomer has stronger fluorescence emission ability.Because the methyl group in L-CHO can increase the interlayer steric hindrance in the COF-HMAT material.Ⅲ.Design and synthesis of two novel dicarboxylic acid organic ligands(containing pyridine oxide groups(L-67-OP)and 2,2,6,6-tetramethylpiperidine oxide(TEMPO)with oxygen radicals(L-67-TEMPO),respectively.The ligands(L-67-OP and L-67-TEMPO)were assembled by solvothermal method with Zr Cl4 to synthesize two crystalline porous materials based on Ui O-67.Both materials crystallize well and have a rich channel.At the same time,we prove the existence of oxygen free radicals in the crystal material Ui O-67-TEMPO,which lays the foundation for studying the heterogeneous catalysis of TEMPO.In summary,we synthesized a series of crystalline materials,and combined the properties of TADF with crystalline materials,which extended the research field of TADF properties and has good research value.