title: Electrostatic Ion Enrichment in an Ultrathin-Layer Cell with a Critical Dimension between 5 and 20 nm.
abstract: Electrostatic interactions play an essential role in many analytical applications including molecular sensing and transport studies using nanopores and separation of charged species. Here, we report the voltammetric quantification of electrostatic ion enrichment in a 5-20 nm thin electrochemical cell. A simple lithographic micro/nanofabrication process was used to create ultrathin-layer cells (UTLCs) with a critical dimension (i.e., cell thickness) as small as 5 nm. The voltammetric response of a UTLC was found to be largely dominated by the electrostatic interaction between charges on the cell walls and the redox species. We show that the ultrasmall cell dimension yielded a 100-300-fold enrichment for cationic redox species. An interesting surface adsorption effect was also demonstrated.
authors.affiliation: Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
authors.forename: Jin
authors.identifier: 0000-0003-0905-0736
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
authors.forename: Bo
authors.identifier: 0000-0002-1737-1241
authors.initials: B
authors.lastname: Zhang
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry; D055664:Electrochemical Techniques; D004573:Electrolytes / Q000737:chemistry; D005898:Glass; D058608:Nanopores; D010084:Oxidation-Reduction; D055672:Static Electricity
chemical_list: D056831:Coordination Complexes; D004573:Electrolytes