PREPARATION OF NiO/YSZ POWDERS USING A PECHINI-TYPE METHOD

• Published in: Materiali in tehnologije Vol. 40; no. 2; pp. 69 - 72
• Main Authors: Razpotnik, Tanja, Francetic, Vojmir, Macek, Jadran
• Format: Journal Article
• Language: English
• Published: 01.03.2006
• ISSN: 1580-2949; 1580-3414

Nickel-oxide-yttria-stabilized zirconia (NiO-YSZ) powder mixtures were prepared using a Pechini-type sol-gel route. Metal chlorides/nitrates and citric or ascorbic acid were used to prepare the metal-carboxylic acid complexes. Their subsequent polyesterification with ethylene glycol at moderate temperatures yielded a homogeneous polymer resin. During the thermal treatment of such a 3D resin up to 900 DGC metal oxides were formed. In order to optimize the process the influence of the anionic part of the metal precursor and the molar ratio of the complexing agent, e.g., carboxylic acid, and the ethylene glycol was studied. The properties of the as-synthesized powders were determined using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and BET surface area analysis. The sintering behaviour of the sample powder mixtures was studied with a heating microscope. The selection of metal chlorides or nitrates for precursors as well as the variations in the molar ratios of all the starting components affected the cross-linking within the polymer and also the characteristics of the NiO/YSZ products. Their properties determine whether they are suitable as anodic materials for solid-oxide fuel cells.