Study On The Construction And Photocatalytic Reaction Of Zn/Ni Coordination Polymers With Photofunction

Coordination polymers have been widely served as catalyst in the photocatalytic due to their large specific surface area,high porosity,and well-ordered crystalline structure.Two coordination polymers were synthesized by solvothermal method with 4,4'-(9,10anthracene diyl)dibenzoic acid(H₂ADBA)as ligand,Zn(?)and Ni(?)as mental nodes,respectively.It was found that two MOFs possessed high photocatalytic activity were applied to catalytic organic synthesis and photocatalytic degradation of organic dye based on characterization and property analysis.The specific research contents and main results are as follows:(1)By optimizing the reaction temperature,pH,time,and metal ions/ligands ratio,a case of coordination polymer,Zn-ADBA,with configuration of alcohol dehydrogenase(LADH)was obtained.Based on the active site of Lewis acid in the structure and the photoactivity given by the LADH-like configuration,it was applied to the cyanosilylation of aldehydes catalyzed by Lewis acid.The experimental results showed that the yield of cyanosilylation of aldehydes is 88.6%,and 82.7%after five cycles of catalysis at room temperature and pressure.Then it was used in the photocatalytic C-C coupling reaction of N-phenyltetrahydroisoquinoline and nitromethane,and the yield reached 97.6%.After five cycles,the yield was still 84.3%.Surprisingly,catalytic efficiency was more than 90%whether electron donor group or electron acceptor group when the substrate was expanded.(2)By adjusting the reaction temperature and time,a case of coordination polymer,Ni-ADBA,was obtained.Single crystal X-ray diffraction analysis shows that the metal ions are bridged by water and ligands with different torsion angles to form a three-dimensional framework.The energy band gap(E_g=2.757e V)was calculated by ultraviolet-visible diffuse reflectance spectroscopy and Kubleka-Mun K formula.The photocurrent response shows that Ni-ADBA has sensitive and stable photocurrent response at room temperature and pressure.Based on above results,Ni-ADBA was applied to the photodegradation of methylene blue(MB)and methyl orange(MO).The experimental results showed that under room temperature and pressure,the degradation rates of MB and MO reached 99.20%and 96.54%,respectively.After five cycles,the catalytic efficiency did not decrease significantly and the structure of Ni-ADBA remained stable.The kinetic results showed that the degradation process of MB and MO conformed to the quasi-first order kinetic model.