The Preparation Of Bismuth Oxide And Studies For Their Electrochemical Performance

Under the promoting of science and technology,electronic equipment,such as mobile phone and portable notebook computer,is developing rapidly.The development of electric vehicles with battery as power source is also rapid.Therefore,it is the key to search for efficient,economical,safe and environmentally friendly energy storage equipment.Among them,alkaline rechargeable batteries and lithium ion batteries which are known as high performance energy storage devices,are widely used in our daily life because of their high energy conversion,easy to use,easy to carry,safe and reliable.In this paper,three kinds of electrode materials of Bi2O3,Fe-Bi2O3 and Cu-Bi2O3 were synthesised and studied as negative electrode materials in Bi2O3//Ni(OH)2,Cu-Bi2O3//Ni(OH)2 alkaline rechargeable battery and Fe-Bi2O3 materials was tested as anodes for lithium ion batteries respectively to study the electrochemical properties.The main contents of this paper are as follows:1.The Bi(NO3)3·5H2O was raw material,and the Bi2O3 material was prepared by precipitation and high temperature calcination.Through orthogonal experiment,when Bi(NO3)3·52O was 0.08 mol L-1,KOH was 1.5 mol L-1,the calcining temperature was 450 ? and the calcining time was 6 h,the Bi2O3 material with the best electrochemical performance was obtained.And then Bi2O3 and the commercial Ni(OH)2 materials were studied as the negative electrode and positive electrode in alkaline rechargeable battery.Under the current density of 1 A g-1,the specific capacity was 226 mAh g-1,and after 500 cycles,the initial specific capacity was 70%.2.The Bi(NO3)3·5H2O was raw material and KOH was precipitant,Cu-Bi2O3 material was prepared by co-precipitation and high temperature calcination.Through the orthogonal experiment,the best performance of Cu-Bi2O3 material was obtained when Cu(CH3OO)2 was used as copper source,ncu/nBi was 0.08,the calcining temperature was 450?,and the calcining time was 6 h.It is assembled with the commercialized Ni(OH)2 electrode material into Cu-Bi2O3//Ni(OH)2 alkaline rechargeable battery.Under the current density of 1 A g-1,the specific capacity was 313 mAh g-1 and 80%of the initial specific capacity was obtained after 500 cycles.3.The Bi(NO3)3·5H2O was raw material and KOH was precipitant,Fe-Bi2O3 material was prepared by co-precipitation and high temperature calcination.Through orthogonal experiment,the best Fe-Bi2O3 material with excellent electrochemical performance was prepared by using(NH4)3Fe(C2O4)3 as the iron source,nFe/nBi=0.1,the calcining temperature was 450?,and the calcining time was 6 h.Under the current density of 100 mA g-1 the initial discharge specific capacity was 1060 mAh g-1 and the reversible capacity of the second lap was 550 mAh g-1,and the capacity was still 285 mAh g-1 after 50 cycles.Compared with the pure Bi2O3 material,the capacity and cycle life of the Fe-Bi2O3 materials are more excellent in electrochemical performance.