| In the dissertation , four mixed-ligand complexes, Cu(mnt)(phen)(mnt -maleonitriledithiolate; phen = 1,10-phenanthroline), Cu(dmit)(phen)(dmit = 1, 3-dithiole-2-thione-4, 5-dithiolate), Zn(dmid)(phen)2 (dmid = 1, 3-dithiole-2-one-4, 5-dithiolate) and Cd(dmid)(phen)2 have been designed, synthesized and characterized. The single crystals of these complexes have been obtained and the structures of these complexes have been determined. The light-oxidation degrading process of Zn(dmid)(phen)2 in pyridine solvent has been observed and discussed. The degradation product of Zn(dmid)(phen)2 in pyridine is mixed-ligand complex Zn(NCS)2(phen)2 and the crystal structure of Zn(NCS)2(phen)2 has been determined by X-ray structure analysis. These layered- stacking structural complexes may have some functions in electronic area and electrochemistry. Therefore, the most popular material in the area of energy resource, LiNi1-xCoxO2, in the pivot of sulfur, is chosen as the object of investigation. The charge-discharge properties of polymers Li2(dmid) and Li2(mnt), and the superficial modification of the relevant compounds to the electrode material LiNi1-xCoxO2 and MnO2 have been discussed.The main results are listed as:1. Two mixed-ligand complexes Cu(mnt)(phen) and Cu(dmit)(phen) have been synthesized and characterized. Their stacking modes are different and interesting. Complex Cu(dmit)(phen) forms the pseudo-dimer by the interactions of coordinated S atom of the ligand dmit and the adjacent metal atoms in Cu(dmit)(phen) complex, then forms two-dimensional structure through the interaction of terminal sulfur in dmit and Cu atom of the adjacent molecular. The Cu(mnt)(phen) complex forms supermolecular through the interaction of sulfur in mnt and Cu atom of the adjacent Cu(mnt)(phen) molecular and the π-π interaction between mnt and phen of the adjacent molecular. The TGA curve indicate Cu(mnt)(phen) is stable below 325℃, much more stable than Cu(dmit)(phen). The EPR results of these two complexes show that axis symmetry of the Cu(II) approximately belongs to C2v point group. Cu(dmit)(phen) also shows the distinguishable hyperfine splitting signal of the cuprum atom. Cyclic voltamogram results indicate that redox behaviors of these two complexes mainly originate from dithiolene ligand. In addition, the oxidation peak of Cu( I )-Cu( II) is observed in Cu(mnt)(phen), while no redox couple of Cu( I )-Cu( II) for Cu(dmit)(phen) complex is detected. Thesekind of mixed-ligand metal complex of dithiolene and diimine, M(S-S)(N-N), based on the ligand supersede synthesis using (N-N) and [M(S-S)2]2" , are easy to obtain single crystals .2. The dithiolene and diimine mixed-ligand complexes M(dmid)(phen)2 ( M = Zn, Cd), have been designed, synthesized and characterized. The crystals of these complexes have been obtained and the structures of these complexes have also been determined. Unlike Cu(dmit)(phen); there is no interaction between S and C=O atom of the ligand dmid and the adjacent metal atoms in M(dmid)(phen)2 complexes. The results of molecular geometry optimization are in agreement with the results of X-ray structure analysis and the main infrared absorptions are also consistent with the practical measure. The two complexes have the same thermal-stable properties and their thermal stability are similar to that of Cu(dmit)(phen). At room temperature, the weak absorption in visible region originates from the transition of LL'CT, and these absorptions are influenced strongly by the solvent. Under the excitation of the ultraviolet, the solutions of M(dmid)(phen)2 show strong fluorescence emission at 410 - 450 nm, and the excitation and emission spectrum shifted to longer wavelength as the polarity of solvent increased (DMSO > DMF > pyridine). The solid strong emission band is in the near 535 nm.3. The light-oxidation degradation processes of M(dmid)(phen)2 (M = Zn, Cd), for example, Zn(dmid)(phen)2 in pyridine solvent has been monitored. It has been found under the light, dmid2" of M(dmid)(phen)2 in pyridine solution could generate NCS" and NCS replaces dmid2" to form M(NCS)2(phen)2 simultaneously. Crystals of Zn(NCS)2(phen)2 and Cd(NCS)2(phen)2 have been obtained and the structure of Zn(NCS)2(phen)2 has been determined. In the crystal of Zn(NCS)2(phen)2, two NCS ligands are arranged in yyn-configuration, and have strong tz-k interaction with the adjacent phen, which result in the mode of layer stacking with holes. The light-oxidation reaction of [Zn(dmit)(phen)]2 is similar to Zn(dmid)(phen)2; the two complexes give the same final results. In the solution SCN-C3H7 and SCN-C4H9had been identified by GC-MS analysis.4. Cathode materials LiNii.xCoxO2 for lithium ion batteries could be obtained by co-precipitation and high temperature solidification synthesis. The results show that these materials have layered structure similar to a-NaFeO2 and uniform morphology and normal grain-size distribution and better electrochemical performance. The first charge-discharge capacity of LiNio.9Coo.1O2 could be up to 251.2 mAh-g"1 and 208.7 mAh-g"1 respectively between 2.7 v to 4.3 v at 50 mAh-g"1, after 20 cycles, its discharge capacity 182.8mAh-g '. Moreover, the dopant of Cobalt in LiNiO2 could stabilize crystal structure and regulate cation distribution in crystal lattice during charge-discharge process. It can improve the cycling performance and thermal stability, and nevertheless, the capacity of charge-discharge decreases with the increasing of Cobalt content.5. For Li2(dmid) and Li2(mnt) polymers, these two polymers have good electrochemical properties when these complexes polymers were fully absorbed by charcoal, the electrochemical performance of Li2(mnt) is better than that of Li2(dmid). The samples could be obtained by direct grind of basic supporting materials LiNiixCoxO2 and complexes modifiers. The samples show the same electrochemical behavior as the supporting materials due to the weak interaction of supporting materials and complexes modifiers. Moreover, the cyclic electrochemical charge-discharge property enhanced when MnC>2 was modified with porphyrazine compounds FePz(dtn)4 and CoPz(dtn)4.
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