Investigation of Ni-based alloy/CGO electro-catalysts as protective layer for a solid oxide fuel cell anode fed with ethanol

Abstract

Ni-based alloys were prepared by using the oxalate method and subsequent in-situ reduction. The crystallographic phase and microstructure of the catalysts were investigated. These bimetallic alloys were mixed with gadolinium-doped ceria in order to obtain a composite material with mixed electronic-ionic conductivity. Catalytic and electrocatalytic properties of the composite materials for the conversion of ethanol were investigated. Electrochemical tests were carried out by utilizing the Nibased alloy/CGO cermet as a barrier layer in a conventional anode-supported solid oxide fuel cell (SOFC). A comparative study between the modified cells and a conventional anode-supported SOFC without the protective layer was made. The aim was to efficiently convert the fuel directly into electricity or syngas (H 2 and CO) just before the conventional anode support. In accordance with the exsitu catalytic tests, the SOFC anode modified with Ni-Co/ CGO showed superior performance towards the direct utilization of dry ethanol than the bare anode and that modified with Ni-Cu/CGO. A peak power of 550 mW cm -2 was achieved with the dry ethanol-fed Ni-Co/CGO pre-layer modified-cell at 800°C. A total low frequency resistance of \0.5 X cm 2 at 0.8 V of cell voltage was recorded in the presence of ethanol directly fed to the SOFC.

Recent Advances in the Development of Anode Materials for Solid Oxide Fuel Cells Utilizing Liquid Oxygenated Hydrocarbon Fuels: A Mini Review

“…Besides the single active‐metal supported catalysts, the alloy‐based catalysts were also investigated as the active anode catalysts for SOFCs operating on ethanol fuel . The crystal structure, microstructure and electro‐activity of a nanosized NiCu alloy‐GDC composite used as an anode catalyst for SOFCs were studied when ethanol was used as the fuel . A PPD of 0.277 W cm −2 was obtained by cell with this alloy catalyst layer in ethanol‐water (1:3) fuel at 800 °C compared with 0.231 W cm −2 for an unmodified cell under the same condition.…”

Material and method selection for efficient solid oxide fuel cell anode: Recent advancements and reviews

“…The structure of particle was cubic, and the components were uniformly distributed. 163 Ni-Cu/CGO 164 and BaZrO 3 (BZO) modified NiO-YSZ 165 anode were synthesized by ball milling. Ni/CGO anode, 85 Ni/YZT, 53 Ni-GDC, 105 Cu-Ni/YSZ anode, 65 and Ni/LLTO anode 166 were prepared using glycine-nitrate process (GNP) (a process in which metal nitrate and glycine are chosen as oxidizer and fuel).…”

Lanthanum Ferrites-Based Exsolved Perovskites as Fuel-Flexible Anode for Solid Oxide Fuel Cells

“…An alternative strategy for SOFC systems’ simplification, which has been quite recently adopted, consists of the use of a functional layer coated on the external side of Ni-YSZ anodes [ 32 ]. Due to the favorable electronic properties, Ni alloys in combination with doped ceria electrolyte have been widely investigated to replace bare Ni [ 33 , 34 , 35 ]. The specific advantage relies on a breaking effect of the crystallographic arrangement of Ni atoms, which is responsible for the cracking mechanism of hydrocarbons [ 36 , 37 ].…”