纳米MnO_2的固相合成及电化学性能(Ⅳ)

Synthesis of nanophase MnO_2 with solid-phase reaction and its electrochemical properties(Ⅳ)

：利用固相反应法制备出纳米ＭｎＯ２，用ＸＲＤ、ＴＥＭ、化学分析、循环伏安、恒流放电等测试手段对样品的性能做了研究。结果表明，样品为隧道结构中不含杂质阳离子的α－ＭｎＯ２，粒径小于５０ ｎｍ ，粒子呈球形。这种纳米ＭｎＯ２ 的电化学活性较高，放电机理与常粒径材料类似，但有更大的放电容量，主要在第二步按溶解沉积机理放电时优势明显。尤其适于重负荷放电，表现出良好的去极化性能。

Nanophase powder α MnO 2 without cations impurity in its tunnels was prepared by solidstate reaction.Its mophology,crystalline type and electrochemical properties were measured by XRD,TEM,chemical analysis,cyclic voltammetry and charge discharge at constant current.The results show that the particle size of the α MnO 2 is less than 50 nm and its shape is spherical.The discharge mechanism of the nanophase α MnO 2 was the same as normal particle MnO 2 but it had higher electrochemical activity and capacity.The favorable depolarization is shown especially in heavy load discharge.