Structural, microstructural, thermal, and electrical properties of Ni/YSZ cermet materials

Abstract

Ceramic-metal composites (cermets) containing 4 mol% yttria-zirconia (4YSZ) and Ni particles as anode materials in solid oxide fuel cells were prepared by two methods. The first method involves nickel oxalate dihydrate precipitation on the 4YSZ powder and decomposition at 360°C in inert Ar atmosphere. The second method consists of impregnation of the 4YSZ pellets with an aqueous solution of nickel nitrate. The temperature of oxalate decomposition was determined on the basis of TG/ DTA experiments. Gaseous products of decomposition were analyzed by mass spectrometry. The structure of the materials was characterized by X-ray diffraction, scanning electron microscopy, porosity studies, and particle size measurements. The thermal expansion coefficient (TEC) was determined by dilathometric method. Electrochemical impedance spectroscopy was used to determine the electrical conductivity. Thus, determined TECs, porosity, and electrical properties were found suitable for anode materials of fuel cells.

Methane steam reforming over Ni/YSZ cermet anode materials synthesized by different methods

“…Nickel-based cermet materials used as anodes in solid oxide fuel cells fed with hydrocarbons or hydrogen typically exhibit high nickel concentrations to allow sufficient electronic and ionic conductivity. 32–34 The chemical compositions of the AQ, ORG and SG NiO/YSZ catalysts were similar. The molar ratio of Ni to Zr of SG was ca.…”

NiO–Ba0.95Ca0.05Ce0.9Y0.1O3−δ as a Modified Anode Material Fabricated by the Tape Casting Method

“…When Ni–YSZ anodes are used for SOFCs, a high porosity (55 wt.%) is necessary to achieve high performance. In previous works [ 35 , 36 ], researchers investigated the impact of total porosity on an Ni–YSZ anode support. In the samples, the anode porosity varied from 32% to 76% in four test cells, and the peak power density varied from 0.72 W/cm 2 (for a porosity of 32%) to 1.55 W/cm 2 (for a porosity of 57%).…”

Synthesis, microstructural properties and chemical stability of 3DOM structures of Sr1−xYxTiO3

“…According to the literature, TEC values for SrTiO 3 (measured 9.4 9 10 -6 K -1 [10], 9.9 9 10 -6 K -1 [11] and calculated 11.1 9 10 -6 K -1 [10]) and YSZ (determined for dense 10.5 9 10 -6 K -1 [12] and porous 9.8 9 10 -6 K -1 [13]) are comparable.…”