Synthesis And Characterization Of New Fluorescent Molecules For Sensing Metal Ion

Organic fluorescent materials have been attracted much attention in the research of optoelectronic information materials for the various advantages compared with inorganic light-emitting diodes.In this dissertation,a series of N,N-bis-(1-aminopropyl-3-propylimidazol salt)-3,4,9,10-perylene tetracarboxylic acid diimide (PDI) and1,3,4-bi-oxadiazoles derivatives for organic light-emitting diodes were designed and synthesized.Then their optoelectronic properties were investigated. Furthermore, sensors based on perylene tetracarboxylic acid diimide group or bi-oxadiazoles as the fluorephore were designed and synthesized.And their chemosensing properties were also investigated.The dissertation was divided into the following parts:Firstly, the water-soluble N,N-bis-(1-aminopropyl-3-propylimidazol salt)-3,4,9,10-pery-lene tetracarboxylic acid diimide (PDI) was synthesized by3,4,9,10-perylene tetracarboxylic dianhydride as the started material. Incorporation of imidazolium ion functionalities into the aromatic backbone of PDI improves the solubility and dispersion stability of PDI in solvents. The resulting compound is soluble in many solvents, such as DMSO, DMF, EtOH/H2O, Acetone/H2O, THF/H2O, etc. Compared with different organic/water solvents, PDI has the strongest fluorescent emission in EtOH/H2O with maximum UV absorption of526nm and maximum fluorescent emission of540nm, respectively. PDI can be used as a new optical probe for sensing Cu2+ions. The sensor based on this probe exhibited rapid and sensitive responses and improved selectivity toward Cu2+ions. TGA shows that PDI is thermally stable. Only5%mass loss is detected when PDI was heated up to353℃.Secondly, A new series of derivatives of symmetrircal bi-oxadiazoles containing azobenzene were synthesized.Their chemical structures were determined by FT-IR,1H NMR. Study of bi-oxadiazoles containing azobenzene photoluminescence characteristics in fluorescence spectra.The result shows, Oxadiazole derivatives of light-emitting intensity is influenced not only by the azobenzene group mol ratio, but also by the concentration of azobenzene group. When azobenzene group reaches a certain level of concentration, the light of system will not effluence; Flexible chain length affect the performance of its light,with the chain length added,azobenzene within the scope of their emission peaks are influential.