title: Nonfaradaic nanoporous electrochemistry for conductometry at high electrolyte concentration.
abstract: Nanoporous electrified surfaces create a unique nonfaradaic electrochemical behavior that is sensitively influenced by pore size, morphology, ionic strength, and electric field modulation. Here, we report 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 strengths.
authors.affiliation: Department of Chemistry, Seoul National University , Seoul 151-747, Korea.
authors.forename: Je Hyun
authors.initials: JH
authors.lastname: Bae
authors.forename: Chung Mu
authors.initials: CM
authors.lastname: Kang
authors.forename: Hyoungseon
authors.initials: H
authors.lastname: Choi
authors.forename: Beom Jin
authors.initials: BJ
authors.lastname: Kim
authors.forename: Woohyuk
authors.initials: W
authors.lastname: Jang
authors.forename: Sung Yul
authors.initials: SY
authors.lastname: Lim
authors.forename: Hee Chan
authors.initials: HC
authors.lastname: Kim
authors.forename: Taek Dong
authors.initials: TD
authors.lastname: Chung
mesh_terms: D003217:Conductometry; D004573:Electrolytes / Q000032:analysis / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D013499:Surface Properties
chemical_list: D004573:Electrolytes