Preparation and Electrochemical Properties of Layered Manganese Oxide(Li-birnessite Type)

采用O2氧化法在碱性条件下氧化Mn2+,制备Li-birnessite型层状MnO2.X射线衍射、扫描电子显微镜、BET、热重等技术表征MnO2样品的性能.以放充电法测试Li-birnessite正极材料性能.结果表明,Li-birnessite结晶良好,层间距约为0.70 nm,呈球状或类球状.以Li-birnessite为正极材料的扣式电池在0.2 C(40 mA/g)条件下放电时容量高达203 mAh/g,且具有良好的倍率性能.Layered Li-birnessite was prepared by means of oxidizing Mn2+ with O2 gas in alkaline media.The as-prepared sample was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),BET and thermogravimetric/diffenential thermal analysis(TG/DTA) techniques.The electrochemical properties of the material were also investigated.The results show that such a Li-birnessite consists of well-crystallized spherical particles with an interlayer distance of 0.70 nm.The Li-birnessite delivered a high discharge capacity of 203 mAh/g at a rate of 0.2 C(40 mA/g),and had good rate capability as well.作者联系地址：福建南平南孚电池有限公司;厦门大学固体表面物理化学国家重点实验室,化学系;厦门大学固体表面物理化学国家重点实验室化学系;Author's Address: 1.Fujian Nanping Nanfu Battery Company Limited,Nanping 353000,Fujian,China;2.State Key Laboratory for Physical Chemistry of Solid Surfaces,Department of Chemistry,Xiamen University,Xiamen 361005,Fujian,Chin