Zeng Zhiyuan, Liang Wen-I, Chu Ying-Hao, Zheng Haimei
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Faraday Discuss. 2014;176:95-107. doi: 10.1039/c4fd00145a. Epub 2015 Jan 19.
We study the lithiation of a Au electrode in an electrochemical liquid cell using transmission electron microscopy (TEM). The commercial liquid electrolyte for lithium ion batteries (1 M lithium hexafluorophosphate LiPF6 dissolved in 1 : 1 (v/v) ethylene carbonate (EC) and diethyl carbonate (DEC)) was used. Three distinct types of morphology change during the reaction, including gradual dissolution, explosive reaction and local expansion/shrinkage, are observed. It is expected that significant stress is generated from lattice expansion during lithium-gold alloy formation. There is vigorous bubble formation from electrolyte decomposition, likely due to the catalytic effect of Au, while the bubble generation is less severe with titanium electrodes. There is an increase of current in response to electron beam irradiation, and electron beam effects on the observed electrochemical reaction are discussed.
我们使用透射电子显微镜（TEM）研究了电化学液体池中金电极的锂化过程。使用了用于锂离子电池的商用液体电解质（1 M六氟磷酸锂LiPF6溶解于1:1（v/v）的碳酸乙烯酯（EC）和碳酸二乙酯（DEC）中）。观察到反应过程中有三种不同类型的形态变化，包括逐渐溶解、爆炸反应和局部膨胀/收缩。预计在锂 - 金合金形成过程中，晶格膨胀会产生显著的应力。由于金的催化作用，电解质分解会产生大量气泡，而钛电极产生的气泡较少。响应电子束照射电流会增加，并讨论了电子束对观察到的电化学反应的影响。
