摘要
采用氧化铝为模板的电化学沉积方法制备锡纳米阵列电极,用扫描电镜和X射线衍射仪表征电极微观形貌结构,并采用循环伏安和交流阻抗研究电极嵌锂过程,同时研究纳米晶锡薄膜电极和轧制锡箔电极。结果表明:纳米阵列电极与锡薄膜、锡箔电极具有不同交流阻抗谱特征,锡纳米阵列电极在中频区出现双电层阻抗,与其电解液/电极接触面积较大有关;不同微观结构形态下锡电极的电化学反应表面阻抗相差大于一个数量级,锡纳米阵列的表面膜电阻为19.8~14.6?·cm2;锡纳米阵列电极上的锂离子扩散速率最大,0.2V嵌锂电位下扩散系数为10-10cm2·s-1;采用纳米阵列结构使电极具有很高电的化学活性。
Tin nano-array electrodes were assembled by electrochemical deposition using alumina anodic oxide (AAO) as templates. Morphology and structure of the tin electrodes were characterized by SEM and XRD. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were applied to reveal the electrochemical performance of the electrodes used as anode of Li-ion battery. Compared to electrodes of tin film and tin foil from rolling, the electrodes of tin nano-arrays are very active. The EIS spectra of tin nano-array electrodes show different characters from electrodes of tin film and tin foil. A medium-frequency area has been found which is ascribed to the large charge transfer area across the electrode/electrolyte interface. The lithium ion transporting in solid-electrolyte ion surface layer are controlled by structure of electrodes. The surface resistances for nano-arrays observed from high frequency ace are between 19.8 and 14.6Ω.cm2. The highest diffusion coefficient is 10^-10cm2·s^-1 for nano-array electrode, at potential of 0.2 V. The nano-array structure can lead to high electrochemical activity of the electrodes.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2012年第9期1628-1632,共5页
Rare Metal Materials and Engineering
基金
云南自然科学基金项目(2007B185M)