Cyclic voltammetry measurements of electroactive surface area of porous nickel: Peak current and peak charge methods and diffusion layer effect

Zhu, Pengcheng ORCID: 0000-0002-0197-7054 and Zhao, Yuyuan ORCID: 0000-0003-2356-8435 (2019) Cyclic voltammetry measurements of electroactive surface area of porous nickel: Peak current and peak charge methods and diffusion layer effect. MATERIALS CHEMISTRY AND PHYSICS, 233. pp. 60-67.

Text
2019_MCP_Peak_charge_final.pdf - Author Accepted Manuscript
Download (960kB) | Preview

Official URL: http://dx.doi.org/10.1016/j.matchemphys.2019.05.03...

Abstract

Surface area is a key parameter for porous metals for electrode applications. Here we measured the electroactive surface area of porous nickel samples using the cyclic voltammetry peak current and peak charge methods. The peak current method measures the contributions from primary pores, while the peak charge method measures the contributions from both primary and secondary pores. The electroactive surface area measured by both methods decreases with normalised diffusion layer thickness. It follows the semi-infinite model at low normalised diffusion layer thicknesses (<0.35) and the thin-layer model at high normalised diffusion layer thickness (>0.35). The correcting factors obtained from the semi-infinite model provide quantitative information on the pore surface roughness and the secondary porosity contribution. The surface roughness of the samples produced by Lost Carbonate Sintering is 2.15. The relative contribution of secondary porosity depends on the type of porous nickel and increases with scan rate, due to reduced diffusion layer thickness. It is in the range of 0.14–0.3 for the samples produced by Lost Carbonate Sintering and loose sintering, and 0.02–0.05 for the sample produced by electrodeposition, for scan rates in the range of 0.005–0.05 V/s.

Item Type:	Article
Uncontrolled Keywords:	Porous metal, Electroactive surface area, Cyclic voltammetry, Diffusion layer
Depositing User:	Symplectic Admin
Date Deposited:	03 Jun 2019 13:20
Last Modified:	19 Jan 2023 00:42
DOI:	10.1016/j.matchemphys.2019.05.034
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3043333