二氧化锰超细粉体的制备及其电化学性能  

Preparation of ultrafine MnO_2 particle and its electrochemical performance

作　　者：李青[1] 胡云楚[1] 汤林[1] 

机构地区：[1]中南林业科技大学理学院,湖南长沙410003

出　　处：《材料热处理学报》2007年第3期31-34,共4页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金项目(30471358);中南林学院引进人才基金(315-0139)

摘　　要：以MnCl2和NaOH为原料,利用超临界流体干燥技术(SCFD)制备了MnO2超细粉体。采用TG-DTA、XRD、粒度分析仪、透射电镜、恒流放电等方法对样品的热稳定性、粒子的形貌、电化学性能进行了表征和测试。研究表明,采用超临界流体干燥技术可以制备出颗粒细、大小均匀的纳米粒子;酸化后的纳米MnO2的电化学性能大大提高,中等负荷放电时,累积容量比电解MnO2提高了24%;重负荷放电时,放电容量提高幅度更大,放电容量较电解MnO2提高110%(-0.9V)。With MnCl2 and NaOH as raw material, ultrafine MnO2 powder was prepared by using supercritical fluid drying (SCFD) technique. The MnO2 powder was examined and characterized by TG-DTA, XRD, particle size distribution, TEM and constant current charge/discharge methods. The results show that nanosize MnO2 particle can be prepared by SCFD method. The electrochemical behavior of the sample treated in suitable concentration sulfuric acid solution is significantly improved. The discharge capacity of the thermal-acidified naonphase MnO2 is 24% higher for middle load discharging and about 110% (-0.9V) higher for heavy load discharging than that of electrolytic MnO2. The most high discharge capacity is observed for nanophase MnO2 electrode at heavy load discharging.

关 键 词：临界流体干燥 γ-MnO2 电化学性能 

分 类 号：O646[理学—物理化学]