摘要
采用共沉淀合成法制备了Bi不同取代量的纳米Ca1-xBixMnO3 -δ,其中烧结温度由TG DTA测试确定 .用原子吸收对其进行了分组分析 ,采用XRD ,TEM对其结构和晶粒的大小及形貌进行了分析 ,并与高温固相法和硬脂酸法制备样品进行比较 .结果表明 ,Bi取代量的不同 ,所得样品的物相也随之发生变化 .但不同制备方法所得样品的物相相同 ,晶粒的平均粒径不同 ,但均属纳米级 .当在碱性溶液 ( 9mol/LKOH)中进行充放电性能测试时发现 ,取代量x =0 .l时Ca1-xBixMnO3 -δ的放电容量为 3 80mAh/g ,与同等条件下国际一号样 (MnO2 )的放电容量 2 48mAh/g相比 ,提高了 5 3 % .在充放电实验中 ,电极的可充性能比国际一号样及无取代的CaMnO3 -δ有很大的提高 .因此有希望作为可充电池阴极的活性材料 .
A series of perovskite-type composite oxides Ca 1-xBi xMnO 3-δ with different substituted Bi amount were synthesized by co-deposition method. The composition and structure of this obtained product was analyzed and characterized through XRD, AAS and TEM. The results showed that the Ca 1-xBi xMnO 3-δ was just Perovskite-type while its crystal form changed with the substitute amount x of Bi. All the prepared samples were nanoparticles. The Ca 1-xBi xMnO 3-δ showed a remarkable electrochemical activities. The discharge capacity of the Ca 1-xBi xMnO 3-δ as the cathode material used in alkaline electrolyte solution arrives 380 mAh/g, which is 53% more than that of the international common sample No. 1 (ICNo. 1 MnO 2). The CV and EIS techniques were adopted to explain the improving electrochemistry of the perovskite-type Ca 0.9Bi 0.1MnO 3-δ. The double-exchange mechanism of charge carriers might be exployed to tackle it.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2004年第23期2355-2360,共6页
Acta Chimica Sinica
基金
国家自然科学基金 (No.2 99630 0 2 )资助项目 .
