High performance novel gadolinium doped ceria/yttria stabilized zirconia/nickel layered and hybrid thin film anodes for application in solid oxide fuel cells

Abstract

Magnetron sputtering under oblique angle deposition was used to produce Ni-containing ultra thin film anodes comprising alternating layers of gadolinium doped ceria (GDC) and yttria stabilized zirconia (YSZ) of either 200 nm or 1000 nm thickness. The evolution of film structure from initial deposition, through calcination and final reduction was examined by XRD, SEM, TEM and TOF-SIMS. After subsequent fuel cell usage, the porous columnar architecture of the two-component layered thin film anodes was maintained and their resistance to delamination from the underlying YSZ electrolyte was superior to that of corresponding single component Ni-YSZ and Ni-GDC thin films. Moreover, the fuel cell performance of the 200 nm layered anodes compared favorably with conventional commercially available thick anodes. The observed dependence of fuel cell performance on individual layer thicknesses prompted study of equivalent but more easily fabricated hybrid anodes consisting of simultaneously deposited Ni-GDC and Ni-YSZ, which procedure resulted in exceptionally intimate mixing and interaction of the components. The hybrids exhibited very unusual and favorable I V characteristics, along with exceptionally high power densities at high currents. Their discovery is the principal contribution of the present work.

A review on recent status and challenges of yttria stabilized zirconia modification to lowering the temperature of solid oxide fuel cells operation

“…The GDC and YSZ (with thickness either 200 nm or 1000 nm) have been applied as discontinuous sheets in Ni-containing ultrathin film anodes production in Garcia-Garcia et al. 117 The thickness of 200 nm is more comparable to the commercially available thick anodes in terms of fuel cell performance. The hybrid discontinuous sheets of GDC and YSZ in Ni was recognized as favorable discovery and expected to have a promising future as they perform high current density and power density.…”

Magnetron Deposition of Anode Functional Layers for Solid Oxide Fuel Cells

“…In order to increase the efficiency of thin-film anodes Garcia-Garcia et al [20] suggested producing Ni-containing anodes comprising alternating layers of GDC and YSZ of 200 nm thickness.Also hybrid anode produced by co-deposition of Ni/YSZ and GDC were tested.The conditions for the deposition of layers did not change as compared with the previous works of the authors [15,19]. In the as-deposited state, multi-layer anodes exhibited the highly porous columnar architecture, with welldefinedboundaries between the NiO/YSZ and NiO/GDC layers (Fig.…”

“…SEM cross-section images of multi-layer thin-film anodes: a)as-deposited, b) annealed in air, c) reduced in hydrogen[20].…”

Study of Electrochemical and Crystallographic Changes During Initial Stabilization of La0.75Sr0.25Cr0.5Mn0.3Ni0.2O3−δ Reversible Solid Oxide Cell Electrode

“…However, there are several problems with the Ni‐cermet composites when used in an RSOC. The coarsening of Ni, carbon deposition, or sulfur poisoning (in case of unprocessed natural gas) can take place during operation, although there are novel strategies to avoid/reduce these effects 4–6. In addition to already mentioned problems, Ni‐cermets have poor redox stability, which results in extreme sensitivity against different changes in operation regime and fuel gas composition 7–9.…”