Crystal Structure, Characterization Of The Copper (Ⅱ) Complexes, And Preparation Of CuO Nanoparticle Based On Phenylacetic Acid Ligand

Single crystal X-ray diffraction provids an accurate, effective way for crystal structural identification, which helps the researchers analyze lots of unknown synthesized crystal structure and study their potential application from the identified crystal structure. As a special sort of crystal, the coordination compound shows out some novel crystal structure and performs kinds of significant properties. More and more coordination are fabricated, which expand the new materials' research field and greatly promote the development of coordination chemistry. By reading extensive literatures, the author summarizes influencing factors, synthetic methods in preparing of coordination compound, and outlines the classification, application. The topic in this thesis were selected from reviewing a large number of literatures. Based on a series of experiments were designed by choosing phenylacetate acid as the organic ligand,2,2-bipyridine and 1,10-phenanthroline as the assistant ligands, and make the copper(Ⅱ) as the central atom, we have obtained four novel coordination complexes: (1)Cu(C8H7O2)2, (2)[Cu(C8H7O2)(C12H8N2)2]·(C8H7O2)·6H2O, (3)[Cu(C12H8N2)(OH)(H2O)]2·2(C8H7O2)·6H2O, (4)[Cu(C12H8N2)(OH)]6·6(C8H7O2)·12H2O.A meaningful exploration to prepare copper oxide nanoparticle by thermal decomposition of 1 is contrived from the investigation of copper(Ⅱ) phenylacetate coordination complex.Suitable single crystals of four complexes have been selected and mounted on a X-ray diffractometer for data collection. The data have been corrected for Lp and multi-scan absorption effects. The structure are solved by using direct method and Fourier syntheses and corrected by full-matrix latest square method. It's considered that 1 contain a carboxy-bridged copper(II) Paddle-Wheel type cluster, and then the Paddle-Wheel unit are bridged by a series ofμ3-O which enable construction of the supermolecular along with [100] direction. There are not any types of water in the crystal structure, soπ-πstacking reaction between neighbor one-dimensional coordination chains is the key to stabilize crystal structure, but not hydrogen bonds. The Cu atoms are each coordinated by two phenanthroline ligands and one phenylacetato ligand to complete a penta-coordinate unit in 2 which is identified to be a mononuclear copper complex. Out of the twelve lattice water molecules complete a chair-like dodecawater (H2O)12 clusters by hydrogen bonds. The resulting dodecawater (H2O)12 clusters are hydrogen bonded to the carboxylate groups of phenylacetate anions to build up 1D anionic chains propagating along [100], which play an important role in construction of crystal structure. 3 is a typicalμ2-OH bridged copper coordination compound, with which phenylaceto ligand don't coordinate. The roles of carboxyl ligand playing are counterions. It's remarkable that complex 3 could convert into 2 by changing the pH of crystal growth solution. The discrete cluster [Cu6(bpy)6(OH)6(H2O)2]6+ in 4 can be regarded as a hexamer consisting of square pyramid CUN2O3 by sharing the oxygen atom ofμ3-OH, in which a stronglyπ…πstacking interaction between the adjacent aromatic rings of the bipy ligands results in high stability for the step-like discrete unit. Theπ…πstacking interaction between the different discrete units leads to formation of two-dimensional networks in the sheets parallel to (001). As it's shown in 2 and 3, the hydrogen bond networks play a very important role in crystal structure of 4. The value of solution is a valid reflection of hydroxyl group, so 3,4 could be abstained easily in alkaline environment (pH> 8).All complex can be characterized by infrared spectra, X-ray powder diffraction, and thermal analysis. The crystal morphology and growth characteristics are simulated by BFDH method from using Material Studio simulation software package. Crystal information file from solving of X-ray single crystal diffraction data make it possible to simulate X-ray powder diffraction data. When compare with the experimental spectra, we notice that crystals of 1-3 have good agreement, while 4 exhibites large deviation. We consider that 4 have a large number of combined water, which makes it easy to lead to distorting of crystal structure when water lost. Thermogravimetric measurements have been carried out from room temperature to 900℃for 1-3 under a flow of nitrogen gas. Thermal analysis presents the initial temperature of decomposition of 1 is 205℃, while 2 and 3 are below 200℃. Thermogravimetric analysis have indicated the thermal decomposition residues of 1-3 are copper oxide.Based on the discussions of 1-4 in crystal structure and properties, non-hydroxy 1 have been chose as the precursor to prepare copper oxide nanoparticle. Powder of 1 has been heated to 300℃,400℃,500℃,600℃respectively at the heating rate of 5℃·min-1 and holding 12 h for completing decomposition. X-ray powder diffraction has been used to characterize the calcined products, presented a monophase copper oxide in the powder. Scherrer equation has been applied to predict the size of calcined powder. The simulated outcomes has revealed the size of nano-CuO is between 107-127 nm. Rietveld refinement of X-ray powder diffraction shows the crystal of CuO products is orthorhombic with cell parameters a=32.36863 A, b=18.01169 A, c=2.78437 A and the fitting parameter Rwp=10.88%, Rp=20.98% in a reasonable range.