Electrochemistry at Nanopores
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Speaker : Prof. Taek Dong Chung
Affiliation : Department of Chemistry, Seoul National University
Title : Electrochemistry at Nanopores
Date : November 11, 2015
Location : Science building 604
Time : 5 pm
Abstract
If electrified surfaces are nanoporous, we bump into a unique nonfaradaic electrochemical behavior that is sensitively influenced by pore size, morphology, ionic strength, and electric field modulation. In this talk, we present the contributions of ion concentration and applied AC frequency to the electrode impedance through an electrical double layer overlap and ion transport along the nanopores. Nanoporous Pt with uniform pore size and geometry (L2-ePt) responded more sensitively to conductivity changes in aqueous solutions than Pt black with poor uniformity despite similar real surface areas and enabled the previously difficult quantitative conductometry measurements at high electrolyte concentrations. The nanopores of L2-ePt were more effective in reducing the electrode impedance and exhibited superior linear responses to not only flat Pt but also Pt black, leading to successful conductometric detection in ion chromatography without ion suppressors and at high ionic strength.