Anode supported SOFC fabricated with functional anode: role of variation of fuel and oxidants

Abstract

Abstract The present study focuses on the efficacy of core-shell nickel (Ni) @ stabilized zirconia (SZ) functional anode towards the oxidation of both hydrogen and reformed methane as fuel in presences of steam as one of the important component. The redox reaction is processed by adsorption on anode catalyst followed by decomposition and charge transfer reaction. This is further accelerated by the extension of triple phase boundary (TPB) regions (Ni/SZ/gas) within (intra-) and inter-anode involving electrolyte. Core-shell Ni@SZ cermet enables the extension of TPB regions in contrast to conventional matrix. Authors have reported four configurations for anode support, wherein the layered structure involving conventional Ni-SZ is placed at the fuel side and layers of Ni@SZ on the top. The thin anode layer in vicinity to the electrolyte with optimized Ni content of 28/32 vol % acts as the primary electrocatalytic layer and shows a maximum current density of ∼4 A.cm−2@0.7 V, 800°C with moist hydrogen as fuel. Multifuel capability in the cell with similar functional anode is demonstrated using 20 % reformed methane with optimum steam/carbon ratio (2:1) having current density of ∼ 1.13 A.cm−2 under similar condition. The findings are correlated using impedence spectroscopy and corroborated with morphological findings.