Synthesis And Properties Of Crystalline Materials Based On Bidentate And Tetradentate Carboxylic Acid Ligands

There are many types of crystalline materials,metal-organic frameworks(MOFs)and hydrogen-bonded organic frameworks(HOFs)have attracted widespread attention in recent years.As an hybrid crystalline material,MOFs are widely used in the fields of adsorption,separation,luminescence,and chemical sensing.The structure of MOFs is mainly determined by two parts:organic ligands and metal ions.In this paper,two kinds of organic ligands and metal ions were adopted to prepare two new MOFs under different conditions,and the performance in sensing and adsorption were studied.HOFs are a class of ordered crystalline materials formed by organic molecular units self-assembly through intermolecular hydrogen bonding.In this paper,a tetradentate carboxylic acid ligand with good fluorescence properties was selected for assembly to form a new structure of HOF,and the properties of fluorescence sensing were studied.The main research results of this paper are list as follows:1.A new MOF,{[Zn2(TCPE)(tta)2]·2DMF·4H2O·2Me2NH2+,HNU-34},was synthesized by the assembly of 1,1,2,2-tetrakis(4-carboxyphenyl)ethylene(H4TCPE),1H-tetrazolium(1H-tta)and Zn2+.And the fluorescence sensing performance of HNU-34 for a nitro-explosive was studied.The results show that HNU-34 can selectively detect a series of nitro-explosives.2.A densely structured HOF(HNU-35)was synthesized by self-assembly of H4TCPE.The research found that HNU-35 has good acid-base stability and thermalstability.In addition,HNU-35 has realized high selectivity and sensitivity to Cr2O72-,CrO42-and MnO4-anions in water.It was also confirmed that HNU-35 also had a good detection effect on actual samples in lake and sea water.3.A novel MOF with paddle-wheel metal unit was synthesized by reacting a nitrogen-containing bidentate carboxylic acid ligand with Cu2+(HNU-36).The adsorption performance of HNU-36 on uranium ions was studied.The maximum adsorption capacity was 576 mg/g.