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通过固相反应制备了单掺Pb、单掺Bi化学修饰MnO2 以及掺Pb和Bi化学修饰MnO2 纳米粉体样品。X射线衍射、透射电镜测试结果表明。所得样品主要为 β MnO2 ,粒径在 3 0～ 5 0nm之间。循环伏安以及循环充放电测试结果表明Pb、Bi的掺入改变了MnO2 的充放电机理。在其循环充放电过程中 ,掺杂物与MnO2 形成了一系列MnyPbx(y =4+ ,3 + ,2 + ;x =0 ,2 + )以及MnyBiz(y =4+ ,3 + ,2 + ;z =0 ,3 + )复合物 ,其共氧化与共还原抑制了电化学惰性物质Mn3 O4的生成和积累 ,使得改性MnO2 的放电容量及循环寿命得到了一定程度的改善
Single-doped Pb, single-doped Bi chemically modified MnO2 and Pb-doped and Bi-modified MnO2 nano-powders were prepared by solid-state reaction. X-ray diffraction, transmission electron microscopy test results show. The resulting sample is mainly β MnO2, particle size between 30 ~ 5 0nm. Cyclic voltammetry and cyclic charge-discharge test results show that the incorporation of Pb and Bi changes the charging and discharging mechanism of MnO2. During the cycle of charge and discharge, the dopants and MnO2 form a series of MnyPbx (y = 4 +, 3 +, 2 +; x = 0, 2 +) and MnyBiz (y = 4 +, 3 +, 2 + ; z = 0, 3 +) complex, co-oxidation and co-reduction inhibited the formation and accumulation of Mn3 O4, an electrochemical inert material, so that the discharge capacity and cycle life of the modified MnO2 were improved to a certain extent