Higher corrections of the Ilkovich equation

Journal article

A short-time asymptotic analysis is performed to establish corrections of the Ilkovich equation, which describes the polarographic response of a dropping mercury electrode. The convective diffusion equation governing diffusion limited reactant flux for small drop times is solved by a regular perturbation based on powers of the sixth root of time. This produces a framework within which higher terms of the Ilkovich equation can be derived systematically. As well as reproducing Ilkovich’s original formula and verifying Newman’s correction of Koutecky’s first-order term, we calculate the second-order term for the first time. The calculation is compared to the Newman–Levich procedure and tested against numerical simulations with finite-element software.

Authors: Chapman, SJ; Monroe, C; Reddy, SKM; Van-Brunt, A; White, RE

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Journal of Electroanalytical Chemistry
• Volume: 925
• Article number: 116899
• Publication date: 2022-10-15
• Acceptance date: 2022-10-10
• DOI: 10.1016/j.jelechem.2022.116899
• ISSN: 1572-6657
• Language: English
• Keywords: transport phenomena; dropping mercury electrode; diffusion; limiting current; FFR; Polarography