Abstract
Imidazolium Ionic liquids (ILs) nano aggregates confined into nanopores of silica gel matrices (ILs-sg) modified electrodes were prepared by sol-gel process and characterized by cyclic voltammetry. Furthermore, the amounts of 15% ~ 28% ILs-sg and nano aggregates coated with ILs silica gel (ILs/sg) were prepared and their conductivities were evaluated by performing electrochemical AC impedance measurements from 20 oC to 80 oC. The abnormal results showed that, 1) comparing with the bulk IL, the confined IL had a positive shift effect of Fc/Fc+ redox potential; 2) when IL confined into a nanospace, the electrochemical stability became poor; 3) the ion conductivity of ILs-sg was 29.6% ~ 136% higher than that of ILs coated silica gel, which could be attributed to the formation of nano ionic liquid network electrolyte. These results not only illustrate that the ILs based silica gel could serve as an excellent support of modified electrode for electrochemical active substance, but also reveal that the findings are helpful to understand the electrochemical phenomena of ILs under a confinement environment.
Graphical Abstract
Keywords
ionic liquids, silica gel, electrochemical behaviors, confinement effect
Publication Date
2014-04-28
Online Available Date
2014-04-17
Revised Date
2013-06-28
Received Date
2013-03-01
Recommended Citation
Zuo-peng LI, Ya-qiong WEN, Mei-xia WU, Yong GUO.
Electrochemical Behavior of Ionic Liquid Confined into Nanopores of Silica Gel Matrix[J]. Journal of Electrochemistry,
2014
,
20(2): 121-127.
DOI: 10.13208/j.electrochem.130301
Available at:
https://jelectrochem.xmu.edu.cn/journal/vol20/iss2/6
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