| The deterioration of water environment globally is one of the most important issue.There is an urgent to develop high-performance materials to remove pollutions from wastewater for ecology and environment.Besides the traditional adsorbents and photocatalysts materials,nowdays,the coordination polymers have been widely used for envieonmental restoration.Coordination polymers,a generalized kind of organic-inoganic hybrid materials,are constructed by virous combinations of different metal atoms and different organic ligands.Coordination polymers exhibit some advantages,including easily tailored structures and easy tenability of pore size and shape,which could facilitate the design of coordination polymers in satisfying the desirable properties.There are two goals in this work.On the one hand,to get a coordination polymer which has high-performance adsorption and separation of pollutant,four coordination polymers with different structure has been designed and synthesized under hydrothermal conditions following the cryatal engineering principle,and characterized by serval instruments.In addition,the adsorption organic dyes experiments have been used to test the performance of these coordination polymers.On the other hand,to solve the problem of low efficiency,agglomeration of photocatalysis powder and separation,ZIF-8 was chosen to prepare membrane to explore the proterty of photocatalysis.These results were briefly described as follows:1.Three coordination polymers,Co（tib）（ADC）2（BUC-60）,Zn3（tib）2Cl6（BUC-61）, [Cu2（tib）2（MoO4）Cl]Cl（BUC-62）,were obtained from the reaction of the same ligand（tib）under hydrothermal conditions.The structure analyses revealed that BUC-60,BUC-61 and BUC-62 possess 0D,1D and 3D structures,respectively. The as-prepared samples were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy,CHN elemental analyses,thermal gravity analyses,and photoluminescence spectroscopy.All of them are thermally stable, only BUC-61 exhibits luminescent activity.BUC-60 and BUC-61 exhibited good adsorption performances towards congo red（CR）and mordant blue 13（MB13）. The maximum adsorption capacities of BUC-60 and BUC-61 toward CR were 1948.6 mg g-1 and 1992.4 mg g-1,respectively,along with those towards MB13 being 563.6 mg g-1 and 208.9 mg g-1,respectively.While BUC-60 and BUC-61 demonstrated poor adsorption activities to cationic MB dye.In addition,BUC-60 and BUC-61 can selectively capture anionic dyes molecules from dyes matrix.2.Considering the barely satisfactory performance of adsorption ability of BUC-60 and BUC-61,another highly stable graphene-like coordination polymers （BUC-17）,prepared based on tib,possesses 2D structures and uncoordinated SO42-anions.BUC-17 used as adsorbent to carry out the adsorption of four typical organic dyes including CR,MB13,MB and sudan I（SI）from simulated wastewater.The results demonsatrated that BUC-17 exhibited excellent adsorption performance towards anionic CR and MB13.The maximum adsorption capacity of BUC-17 towards CR and MB13 was 4923.7 and 850.5 mg g-1 at room temperature,respectively.And BUC-17 was inhospitable to cationic MB and neutral SI.The adsorption process followed a pseudo-second-order kinetic model and fitted well with the Langmuir isotherm.The adsorption reaction of CR by BUC-17 was endothermic,spontaneous precesses,and tended to be disordered,which could be affirmed by thermodynamic function.It could be further used to fix SPE column to conduct rapid separation of anionic dyes from organic matrix（CR/MB,MB13/MB）.The possible mechanisms were proposed, including the positive surface charge,ion-exchange,hydrogen-bonding interactions,andπ–πstacking interactions along with the effect of mesopores.3.Inspired by the photocatalytic properties of ZIF-8,a simple,versatile,and powerful synthesis strategy was chosen to prepare ZIF-8 membranes.The ZIF-8 membranes were prepared on polydopamine-modified supports（α-Al2O3 supports） and characterized by powder X-Ray diffraction and scanning electron microscope. The photocatalytic activities of degradation of MB in ZIF-8 membranes under UV light irradiation were determined,and the results revealed that ZIF-8 membranes can decompose MB efficiently.The degradation efficiency is up to 96.8%,much higher than ZIF-8 powder in the same condition.This method could increase the solar energy utilization efficiency of photocatalyst and solve the problem on reunite of powder.The recyclability and stability of ZIF-8 membrane was test by circultating runs in the photocatalytic degradation. |
