Study On The Preparation And Properties Of Luminescent Benzothiadiazole-byridine Derivative Crystals

Rigid ?-conjugated 2,1,3-benzothiadiazole(BTD)is an excellent chromophore.Due to its easy-to-modify feature,the structure of BTD is adjustable.Therefore,various derivatives synthesized by different methods show diverse luminescence behaviors.Recently,BTD-based derivatives have showed the bright application prospect in different areas,including nonlinear optical materials,organic light-emitting diodes,solar cells,fluorescent molecules probes and supramolecular self-assembly.In this thesis,to consider the excellent luminescence and easy crystallization characteristics of the BTD unit,we prepared a series of BTD-based derivative crystals through appropriate reactions and studied their interesting luminescence behavior.This thesis contains two parts as follow:1)As precursors,4,7-bis(2-aminopyridine)-2,1,3-benzothiadiazole(L1)react with copper halide salts to obtain the crystals of three new Cu-BTD complexes(C1,C2 and C5)through in-situ solvothermal reactions.Moreover,the synthesis mechanism and their luminescence behavior are studied.2)As a precursor,4,7-bis(2-aminopyridine)-2,1,3-benzothiadiazole(L1)is protonated by different protonation reactions to obtain three new ionic crystals(1,2,3).In this case,protonation in different positions and using the different anions(Cl-,NO3-)can regulate the assembly of protonated L1 molecules,thereby constructing the special structures of ionic crystals 1-3.Furthermore,we studied their solid-state luminescence behavior.Interestingly,1-3 all show the reversible piezochromic properties with good sensitivity.