Study On The Preparation And Electrochemical Property Of Nano-materials Of Transition Metal Oxides

In recent years, nanocomposite materials were a hot topic owing to theirs much many particular properties such as mechanics,heat,optics, sound, electricity,magnetism and others. However, nano-materials of transition metal oxides also have much particular properties. Recently, nanoparticles formed from transition metal oxides have attracted increasing attention owing to their potential in a variety of fields such as the process of chemical engineering, materials and environmental protection. Furthermore, the synthesis of novel functional nanomaterials not only had theoretical values, but also had an optimum application prospect.Base on the excellent characteristics of transition metal oxide nanomaterials and its electrochemical properties, the paper focuses on the following works: 1. In this article, scalable synthesis of Cu O micro-shuttles is achieved through a facile solvothermal process, its structure and electrochemical performance were measured by X-ray diffraction, scanning electron miscro-scopy, charge/discharge test and electrochemical impedance spectroscopy. When investigated as anode materials for LIBs, the Cu O micro-shuttles deliver a high discharge capacity of 484 m Ah g-1 over 100 cycles at a current density of 100 m A g-1. The improved electrochemical performance can be attributed to its unique shuttle-like structures, which largely reduce the diffusion path of lithium ions and electrons, and also buffer volume expansion during the charge/discharge processes.2. The α-Fe2O3/C composite was prepared by mechanical ball-mixing reaction, characterization means such as X-ray diffraction, scanning electron microscopy, charge/discharge test determined on its structure and electrochemical performance. The results shown that the α-Fe2O3/C composite showed the better reversible charge capacity of 934.8 m Ah g-1 after 50 cycles periods, and had better cycle performance compared with α-Fe2O3 without C. The results of electrochemical properties indicated that there appeared three semicircles respectively representing the Li-ion migrated solid electrolyte interface film,electrical conductivity and charge transfer in the first lithiation, and their evaluative principles were also examined.