Synthesis And Electrochemical Properties Of Zinc Oxide Groups

Currently,the most popular types of electrochemical energy storage devices are lithium-ion batteries?LIBs?and supercapacitors,the negative electrode material is one of the important factors to affect the electrochemical performance.So people usually go through some methods to improve the electrochemical properties of the metal oxide materials,such as the thin film,micro-nanostructured,the carbon-coated and compound modified the negative electrode materials.Micro-nanostructured technology can effectively increase the surface area of the materials and prevent the agglomeration,compound modified can combine the advantages of each metals.These ways can improve the electrochemical properties of the material.In this thesis,ZnO microspheres,which composed of irregular nanoparticals,have been synthesized successfully from a metallorganic precursor.And make the comparison of electrochemical properties with the Zn O synthesized from the inorganic precursor.It is found that the ZnO microspheres synthesized from a metallorganic precursor have the stable structure,and have the good specific capacity and good capacity retention rate as the anode material for lithium ion batteries.The ZnO powders as electrode materials for supercapacitors show high specific capacitances 1123 F/g at the current density of 2 A/g.The ZnCo₂O₄ material obtained by compound modified on the basis of synthetic method from a metallorganic precursor.And make the comparison of electrochemical properties with ZnO and Co₃O₄ materials with the same synthetic method.It is found that the ZnCo₂O₄ materials have the good capacity retention,the excellent cycle performance and high rate performanceas as the anode material for lithium ion batteries.And the ZnCo₂O₄ powders as electrode materials for supercapacitors show high cycling stability,the specific capacitance keeps 234 F/g during 3000 cycles at the current density of 12 A/g.