An Investigation on the Structure of Au(111)/Imidazolium-Based Ionic Liquid Interface: Effect of Alkyl Side Chain Length

Authors

Li CHEN, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Shuai LIU, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Mian-gang LI, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Jian-jia Su, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Jia-wei YAN, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;Follow
Bing-wei MAO, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;Follow

Corresponding Author

Jia-wei YAN(jwyan@xmu.edu.cn);
Bing-wei MAO(bwmao@xmu.edu.cn)

Abstract

In this work, we comparatively investigated the interfacial structures at Au(111) electrode surfaces in two ionic liquids (ILs) with different alkyl chain lengths by combining AFM force curve technique and electrochemical methods. The number and stability of the layering structures, and their potential-dependency were analyzed. The experimental results indicated that the tendencies of force-potential curves in the two ILs behave the same way. At potentials close to PZC, the ions arrange loosely, which lowers the stability of the layering structure. As the potential shifting away from PZC, more ions attach to electrode surface, which increases the stability of layering structure, while further increase of the ions will weaken the stability because of the lattice saturation of ions. However, the location of the alkyl chain at potentials negative to the PZC differs from that at potentials positive to the PZC, leading to an adverse effect on the stability at negatively charged surface and a synergistic effect on the stability at positively charged surface, respectively.

Graphical Abstract

Keywords

ionic liquids, electrochemical interface, atomic force microscopy, force curve

DOI Link

https://doi.org/10.13208/j.electrochem.180148

Publication Date

2018-10-28

Online Available Date

2018-10-15

Revised Date

2018-08-30

Received Date

2018-07-21

Recommended Citation

Li CHEN, Shuai LIU, Mian-gang LI, Jian-jia Su, Jia-wei YAN, Bing-wei MAO. An Investigation on the Structure of Au(111)/Imidazolium-Based Ionic Liquid Interface: Effect of Alkyl Side Chain Length[J]. Journal of Electrochemistry, 2018 , 24(5): 511-516.
DOI: 10.13208/j.electrochem.180148
Available at: https://jelectrochem.xmu.edu.cn/journal/vol24/iss5/9

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