title: Determining Electrochemical Surface Stress of Single Nanowires.
abstract: Electrochemical surface stress is important in nanomaterials because of their large surface-to-volume ratios, which lead to unique mechanical and electrocatalytic properties, but directly measuring this quantity has been challenging. Here we report on experimental determination of the surface stress, and associated electrochemical processes of a single gold nanowire with an optical imaging technique. We show that surface stress changes linearly and reversibly with the potential between 0 and 0.8 V versus Ag/AgCl, but abruptly with large hysteresis, associated with the oxidation and reduction of the nanowire, between 0.8 and 1.5 V. The potential derivative of the surface stress closely resembles the cyclic voltammograms. We described the observations in terms of anion adsorption and surface oxidation/reduction. This work demonstrates a new approach to study electrochemical processes and the associated surface stress changes of nanomaterials.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ, 85287, USA.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Shan
authors.affiliation: Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ, 85287, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Yu
authors.affiliation: Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ, 85287, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Theoretical Chemistry, University of Ulm, 89069, Ulm, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schmickler
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.|Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ, 85287, USA.
authors.forename: Nongjian
authors.initials: N
authors.lastname: Tao
keywords: anion adsorption; electrochemistry; electrostatic repulsion; gold nanowires; surface stress