Characteristics of NiO-YSZ anode based on NiO particles synthesized by the precipitation method

In order to increase the three phase boundary (TPB) length through lowering the NiO particles to submicro-size, NiO powder was synthesized by the precipitation method and the Corresponding NiO-YSZ (8 mol% yttria-stabilized zirconia) composite anodes were investigated in this paper. The crystallite size of the as-synthesized NiO particle was 20-30 nm. The particles were agglomerated, but the agglomerates could be partially broken by grinding. The powder has an average particle size of 0.36 mu m after grinding. NiO-YSZ anodes were fabricated by mixing the as-prepared NiO with commercial YSZ powders together. In order to form suitable porosity, flour was used as the pore-former, which played a key role in affecting the anode performance. Characteristics of the anodes, namely, shrinkage behavior, temperature-programmed reduction (TPR) measurement at a constant temperature (i.e., a modified TPR technique) and resistance characteristic during reduction were investigated. The maximum power density of the anode-supported YSZ film single cell was 905 mW/cm(2) at 750 degrees C based on the Anode-30 (NiO, YSZ and flour was mixed in the weight ratio of 5:5:3). As a summary, high cell performance could be achieved at reduced temperature with the as-fabricated NiO-YSZ anode containing a suitable microstructure. (C) 2007 Elsevier B.V. All rights reserved.