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LİSANSÜSTÜ ARAŞTIRMALAR SEMPOZYUMU & TANITIM GÜNLERİ 2018

Development of NiO-YSZ Precursors for Solid Oxide Fuel Cell Anode Fabrication

Buse BiLBEY, Gamze EROL, Aligül BÜYÜKAKSOY
Malzeme Bilimi ve Mühendisliği ABD

ÖZET
Solid oxide fuel cells are an efficient and environmentally friendly alternative to the conventional

hydrocarbon-based technologies. For high performance SOFC operation, it is imperative that the fuel
electrode(anode) allows fast electrochemical reactions. The most widely preferred anode material is a porous
composite called cermet, composed of an electro-catalytic metal (Ni) and an ion-conducting ceramic (Yttria stabilized
zirconia-YSZ). The electro-oxidation of fuel takes place at the intersection of the Ni-YSZ and gas phases (i.e., triple
phase boundary).

The conventional method to fabricate Ni-YSZ anodes involve the mixing of NiO-YSZ powders, followed by
sintering at high temperatures and in-situ reduction of NiO to Ni. The use of high sintering temperatures result in
coarse microstructures and, thus, short TPB length. Therefore, in present study, we attempt to use the versatile
polymeric precursor method, to which allows the fabrication of powders as well as thin films, with Ni and YSZ phases
being distributed very homogeneously in both cases. The fact that phase formation does not require high-T
calcination and the molecular level mixing that takes place in this method allows fine particle sizes and thus long-
TPBs upon the final anode structure formation. After prepare a polymeric precursor we can produce an anode two
different ways. One of them is with thin film coating by spin or dip coating. Other way is polymeric precursor
calcinated and produce a paste for coating. Particle size is smaller and triple phase regions are longer than traditional
production with polymeric precursor method. Because of that we achieve better fuel cell performance.

In this present study, crystal structure of the powders derived from polymeric precursor were determined
via x-ray diffraction analysis, particle size distribution analyzed, while their morphology, and elemental distribution
were examined by scanning electron microscopy. The SEM analysis also revealed homogeneous NiO-YSZ thin films
well-bonded to YSZ substrate.
Anahtar Kelimeler: Solid Oxide Fuel Cells, Polymeric Precursor Method, NiO-YSZ Based Anodes.

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