Preparation Of Anode Materials Based On Metal Organic Compounds And Study On Its Properties

Lithium-ion battery is a kind of widely used and rapidly developing energy storage devices,with high operating voltage,good energy density,great safety performance,low self-discharge rate and no memory effect.As for the lithium-ion battery,the electrode material is one of the key factors to determine the performance of the battery.And the composite materials prepared by using graphene as the substrate are the hot research topics recently.In consideration of phthalocyanine and metal phthalocyanine compounds are a sort of special metal organic compounds,with 18?-electron planar conjugated aromatic system,we choose metal phthalocyanine compounds and graphene to prepare porous graphene composite materials in this paper.The details of the specific work and conclusions are as follows:(1)Porous Cu/graphene composite materials were prepared by mixing the hyperbranched CuPc which is made from Bph with GO and then sintered at high temperature.The complete morphological characterization and systematic electrochemical tests were also carried out.We can draw the following preliminary conclusions through the relevant test data:under the condition of constant mixing ratio(m(GO):m(CuPc)=1:1),the sintering temperature has a great influence on the porous composite materials of hyperbranched CuPc/graphene.The data analysis shows that the optimal sintering temperature is 800?.The final product has a large number of holes and these holes are close-packed at this temperature,which corresponds to the best electrochemical performance.The first discharge capacity can reach 920mAh/g at 0.1C,and after 100 cycles maintained at about 400mAh/g,with good cycling performance and excellent rate performance.(2)Porous CuO/graphene composites were prepared by a simple two-step method.Through the relevant characterization and electrochemical test data,it can be seen that the different proportions of CuPc and GO have a great impact on the materialsunder the premise of controlling the sintering temperature.The data analysis shows that m(GO):m(CuPc)=1:1 is the best mixing ratio,and the porous structure of the final product is closely arranged with many pores that corresponding to the best electrochemical performance at this ratio:the first discharge capacity is up to 1056.6mAh/g at 0.1C,and the capacity maintained about 610mAh/g after 36 cycles,showing good cycle performance and high capacity retention.(3)The porous composite materials of NiO/graphene were synthesized by a preparative method similar to the previous two chapters.The correlative characterization and electrochemical test data showed the following preliminary conclusions:with the sintering temperature is invariable,the composites were affected greatly with the different proportions of NiPc and GO.The data analysis shows thatm(GO):m(NiPc)=1:1 is the best mixing ratio with excellent electrochemical performance,and we can obtain the porous structure with a dense array of pores at this ratio.The first discharge capacity is 733mAh/g,after 100 cycles can be maintained at about 430mAh/g,also showing good cycle performance and high capacity retention.