Numerical model of Co-Electrolysis in Solid Oxide Cells with Ni/Gd-Doped Ceria (CGO) fuel Electrode

Abstract

The co-electrolysis of atmospheric carbon dioxide with steam is seen as a potential source of synthesis gas. The electrochemically active electrode area on Ni/Gadolinium-doped ceria (CGO) electrodes extends from triple phase boundary (TPB) between Ni, CGO and gas to the double phase boundary (DPB) between CGO and gas. The proposed numerical model of a commercial electrolyser cell aims to reveal main kinetic mechanisms responsible for the electro-reduction at the Ni/CGO fuel electrode. In order to identify main reaction pathways, electrochemical experiments with two types of fuel electrode were performed: porous CGO and mixed Ni/CGO electrode. In this work preliminary results for a mechanism explaining steam electrolysis at the Ni/CGO electrode are presented.