Impedance response of electrochemical interfaces: part II-chemisorption

作者：Jun Huang, Chenkun Li · 发表于：Journal of Physics Condensed Matter · 年份：2021 · DOI：10.1088/1361-648x/abef9d · 被引用次数：17 · 研究领域：Electrochemical Analysis and Applications、Spectroscopy and Quantum Chemical Studies、Electrostatics and Colloid Interactions

Abstract Physical modeling helps to acquire fundamental insights from experimental data when electrochemical impedance spectroscopy is employed for mechanistic understandings of electrocatalytic reactions. Herein, we report an analytical model for chemisorption impedance with a consistent treatment of ion transport in the solution and electron transfer on the electrode surface. Our formulation avoids both a priori decoupling of double-layer charging and electron transfer reaction, and a strict separation of double-layer charging and ion transport. Ion transport in the entire solution region is described by the Poisson–Nernst–Planck theory and electron transfer kinetics on the electrode surface by the Frumkin–Butler–Volmer theory. Surface dipoles caused by partially charged chemisorbates are considered. The classical Frumkin–Melik–Gaikazyan model for chemisorption is retrieved as a limiting case. The obtained formula is validated using experimental data of hydrogen adsorption at Pt(111). Characteristic frequencies and asymptotic behaviors of chemisorption impedance are analyzed.