Development of new catalytic function by surface fluorination of graphite

用平均diameters制作的表面荧光粉， 7、25和40 μm在80-520℃由元素荧光制成，并在1摩尔dm D1-3 D1 LiClO D24 D2 ethylene carbonate/diethyl carbonate （1：1）溶液。Fluorine的内容比我少。XPS在6 - 15%之间获得了基本分析和表面荧光浓缩的2 at%。碳-氟键合是离子键和共轭键之间的中间体，并通过增加荧光温度来接近共轭键。拉曼光谱仪揭示了表面紊乱是由荧光引起的。Graphite samples with average diameters 7、25、40？m have the reversible capacities of 360、350 and 330 mAhg D1 -1， respectively at 60 mAgg D1 -1， however all the fluorinated samples have shown the larger capacities of 380 ~ 400 mAhg D1-1 than the theoretical value 372 mAhg D1-1。capacity and reaction rate increase would be due to increase in surface areas and formation of surface pores for lithium accumulation. NMR study on C-F bonding has indicated that carbon-fluorine bond is ionic in the region of x>8 in C-D2x-D2F and semi-ionic nature increases with decreasing x.氟醚和氟醚的添加剂增加到EC/DEC的石墨电极的可逆能力。

Surface fluorination of graphite powder with average diameters, 7, 25 and 40 μm has been made by elemental fluorine at 80-520℃, and the electrochemical intercalation and deintercalation of lithium ion has been investigated in 1 mol dmィイD1-3ィエD1 LiClOィイD24ィエD2 ethylene carbonate/diethyl carbonate (1:1) solution. Fluorine contents were less than ca. 2 at% by elemental analysis and surface fluorine concentrations obtained by XPS were 6〜15 at%. Carbon-fluorine bonding is intermediate between the ionic and covalent, approaching the covalent bond with increasing fluorination temperature. Raman spectroscopy revealed that surface disorder is increased by fluorination. Graphite samples with average diameters 7, 25, 40 μm have the reversible capacities of 360, 350 and 330 mAhgィイD1-1ィエD1, respectively at 60 mAgィイD1-1ィエD1, however all the fluorinated samples have shown the larger capacities of 380〜400 mAhgィイD1-1ィエD1 than the theoretical value 372 mAhgィイD1-1ィエD1. The capacity and reaction rate increase would be due to increase in surface areas and formation of surface pores for lithium accumulation.NMR study on C-F bonding has indicated that carbon-fluorine bond is ionic in the region of x>8 in CィイD2xィエD2F and semi-ionic nature increases with decreasing x. Addition of fluoroester and fluoroether to EC/DEC increases the reversible capacities of graphite electrode.