锌离子电池正极纳米片材料制备和电化学性能研究

Manganese Dioxides Nanosheets/Graphene as the Zinc-ion Intercalating Materials for High Capacity Zinc Ion Battery

锌离子电池是一种环保、廉价、安全的新型电池,它的电化学行为是正极二氧化锰通过锰的价态转换来存储二价锌离子。二氧化锰作为锌离子电池的正极材料,由于其比表面积大、导电性差等特点导致其容量并不能充分发挥。采用自反应反胶束法制备的二维超薄二氧化锰(Mn O2)纳米片作为一种储存锌离子的材料,从整体上提高锌离子电池的容量。以二维超薄二氧化锰(Mn O2)纳米片为正极的锌离子电池,当电流密度为0.1 A/g时,最高容量达到484.2 m A·h/g,接近锌离子电池的最大理论容量616 m A·h/g;当电流密度为5 A/g时,电池循环两百圈后的容量保持率也有80%,表现了很好的循环性能。

Zinc ion battery is a new battery which is environment friendly, inexpensive and safety; its energy storage mechanism is to store divalent zinc ions in manganese dioxide tunnel by conversion of tetravalent manganese to trivalent manganese. Manganese dioxide is as active material to provide the energy for the cell. However, due to its large surface area and poor conductivity characteristics, the theoretical capacity cannot be fully realized. Therefore, we utilize ultrathin two-dimensional nanosheets manganese dioxide （MnO2） as a new zinc-ion intercalating material produced by a self-reacting microemulsion method to improve the capacity of the zinc ion battery. At a current density of 0.1 A/g, the maximum capacity is 484.2 mA？h/g, which is very close to the theoretical capacity of the zinc-ion battery. At the current density of 5 A/g, the capacity retention rate is still 80% after two hundred cycles, which shows good cycle performance.