Synthesis Of Metal Complexes With Aggregation-induced Emission Properties And Their Application In Calcium Alginate Composite Fiber

Compared with other AIE systems,metal organic complexes with aggregation induced luminescence（AIE）have the advantages of adjustable structure,high quantum luminescence efficiency,controllable color regulation and good photothermal stability.They are widely used in emerging fields such as organic light-emitting diodes,electrochemistry,chemical sensing,biosensors,intelligent materials and so on.Up to date,the reported metallic species for luminescent organometallic complexes（including AIE materials）were all heavy metals,and the organometallic luminescent complexes with light metals had not been reported.β-Diketones could form complexes with metal ions,which have stable chemical properties and excellent luminescence properties.The research of metal complexes with AIE properties also broadens the application prospect of intelligent fluorescent fiber materials.Because the intelligent fluorescent fiber material has the advantages of simple operation and fast response,it has potential application value in the fields of anti-counterfeiting and information encryption.More and more researchers have shown strong interest in this field.Based on the above research background,metal organic complexes with AIE properties were prepared and applied them to the preparation of alginate textile and nano-fibers.In this work,a novel organomagnesium complex（Mg（DBM）₂）with outstanding aggregation induced emission（AIE）properties was synthesized using dibenzoylmethane（DBM）as the ligand.The structure was determined by NMR,FT-IR,XPS and other characterization.At the same time,the single crystal data confirmed that the complex was coordinated by one magnesium ion coordinated to the diones groups of two DBM molecules,and the magnesium ion adopted a distorted octahedrally geometry.The properties of complexes were investigated by UV-vis absorption and fluorescence emission spectroscopy,cyclic voltammetry and density functional theory calculations.Moreover,the Mg（DBM）₂ solution dispersed in fifilter paper was nearly colorless,which could be made into a convenient anti-counterfeiting and encryption tool.Mg（DBM）₂/alginate fibres was prepared by wet-spinning method,which had the advantages of non-toxic,low cost,high efficiency and fast reaction to analytes.It can be used to detect sweat.Cadmium ion(Cd²⁺)was a very harmful heavy metal ion,which caused serious harm to human and environment.Its detection methods have been widely studied.Adding AIE material into nanofiber membrane can provide high fluorescence stability and sensitivity.In this study,a highly sensitive and selective fluorescent nanofibrous membrane（SA@Mg（DBM）₂）for the detection of cadmium ions（Ⅱ）was prepared via electrospinning and Ca Cl₂ crosslinked.The detection range was determined by the change of fluorescence intensity,and its detection mechanism and detection persistence were characterized and described.Therefore,SA@Mg（DBM）₂ can be developed as a rapid,portable and stable sensor for the detection of Cd²⁺.β-Diketone ligand showed interesting luminescence properties after coordination with d¹⁰ Zn（Ⅱ）.Zinc acetate and DBM were used as reaction solvent,and the metal zinc fluorescent complex was prepared under the condition of ice bath by nitrogen protection method.It was named Zn（DBM）₂（CH₃O）₂.The chemical structure,microstructure and photophysical properties were characterized in detail.Metal zinc complexes can be used as temperature sensors and metal ion detection sensors.