ε-VOPO4:: Electrochemical synthesis and enhanced cathode behavior
ε-VOPO4:: Electrochemical synthesis and enhanced cathode behavior
复制标题
DOI：
10.1149/1.1862265
复制
发表时间：
2005-01-01
影响因子：
3.9
通讯作者：
Whittingham, MS
中科院分区：
文献类型：
--
作者：
Song, YN;Zavalij, PY;Whittingham, MS
通过质子在非水电解质和水电解质中的电化学脱嵌以及通过H2 VOPO 4的热分解，从单斜晶和四斜晶形式的H2 VOPO 4合成ε-VOPO 4。如此形成的ε-VOPO 4容易且可逆地与多达两个锂离子反应。来自四氢呋喃前体的ε-VOPO 4在其较高电压平台上具有超过130 mAh/g的可逆容量，并且甚至在2 mA/cm（2）的循环速率下具有95 mAh/g的容量，与尖晶石LiMn 2 O 4的容量相当。ε-VOPO 4的电子电导率为1 × 10（-6）S.cm（-1），锂化学扩散系数在1 × 10（-11）至5 × 10（-9）cm（2）s（-1）的范围内，这取决于组成。在脱氢和嵌锂过程中，结构变化很小，并且这种变化是可逆的。(c)2005年电化学学会。
epsilon-VOPO4 was synthesized from the monoclinic and tetragonal forms of H2VOPO4 by the electrochemical de-intercalation of the protons in both nonaqueous and aqueous electrolytes, as well as by the thermal decomposition of H2VOPO4. The epsilon-VOPO4 so formed readily and reversibly reacts with up to two lithium ions. The epsilon-VOPO4 from the tetragonal precursor has a reversible capacity exceeding 130 mAh/g on its higher voltage plateau, and even at a 2 mA/cm(2) cycling rate has a capacity of 95 mAh/g comparable to that of the spinel LiMn2O4. The electronic conductivity of the epsilon-VOPO4 is 1 x 10(-6) S.cm(-1) and the lithium chemical diffusion coefficients is in the range of 1 x 10(-11) to 5 x 10(-9) cm(2) s(-1) depending on composition. The structure changes little during hydrogen removal and lithium intercalation, and the changes are reversible. (c) 2005 The Electrochemical Society.