Synthesis, Characterization And Application Study Of Several Coordination Polymer Micro/Nano-Materiais

In recent years, owing to their novel structures and ellcellent properties, haveattracted large attention because of their special property in many areas. It has beenshown that they would likely to be widely used in the field of catalysis, spin-crossover, template agent, biological sensing, medical imaging and anti-cancer drugcarriers. Coordination polymer nanomaterials provide an exciting prospect for thedevelopment of a new generation of functional nanomaterials. In this thesis, severalrare earth compounds and octahedron-shaped Zn(Ⅱ)-organic coordination polymershave been prepared successfully via various methods such as solvothermal methodsand microwave treatment. The as-obtained products were characterized by X-raydiffraction (XRD), X-Ray photoelectron spectroscopy (XPS), Fourier-transforminfrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmissionelectron microscopy (TEM), high-resolution TEM (HRTEM), selected area electrondiffraction (SAED), and photoluminescence (PL). The formation mechanism andoptitcal properties of the products were briefly discussed.The main contents are listed as following:(1) Zn(Ⅱ)-organic coordination polymers octahedrons: synthesis, characterizationand the conversion to zinc oxide.Octahedronl ZnO superstructures were simply synthesized by solid-statetransformation of Zn(Ⅱ)-organic infinite coordination polymer particles (ICPs) at550oC. The well-crystallized ZnO nanoparticles exhibit visible emission centred at575nm, representing stable visible photoluminescence from relatively large ZnOnanoparticles in the solid state. The possible mechanism of strong visible emissionwas also proposed. It turned out that oxygen vacancies and Zni-shallow donor play animportant role in the visible emission based on the results of electron paramagneticresonance (EPR) spectra. This solid-state transformation method provides a newapproach to synthesize ZnO nanoparticles with different morphology.(2) Uniform europium-based infinite coordination polymer submicrospheres:Fast microwave synthesis and characterizationUniform europium-based infinite coordination polymer (ICP) submicrosphereshave been prepared from pyridine-2,5-dicarboxylic acid and europium nitrate via afacile and fast microwave heating method in5min, using N,N-dimethylformamide(DMF) as solvent. SEM and TEM results show that the submicrospheres are withdiameters of200-400nm. Furthermore, the surface of the microspheres is smooth andthe submicrospheres are solid. The luminescent properties of the products were alsostudied(3) Europium coordination polymers micro/nanostructures: A ligand structureeffect Several micro/nanostructures of europium coordination polymers built with threeisomers of benzenedicarboxylic acid (phthalic acid, isophthalic acid and terephthalicacid) have been prepared via a simple solvothermal reaction. SEM results demonstratethat the morphologies of the products differ sharply from each other with the variationof the ligand. It was also found that the photoluminescence intensity of the productbuilt from terephthalic acid is much stronger than the other two built from phthalicacid and isophthalic acid. It turns out that the morphologies and properties of theproducts are ligand structure-dependent.