Microstructure stability studies of Ni patterned anodes for SOFC

Impedance Spectroscopy Analysis of Ni/YSZ Interfaces Prepared by Liquid Precursor Deposition

“…Evidently, the 1.1 µm thick Ni film (thickness determined from SEM analysis, not shown here) is quite stable at 700 °C under humidified H 2 , which allowed electrochemical measurements to be carried out, all at the open circuit potential (OCP). Similar results were reported for sputtered Ni films with an ~800 nm thickness on YSZ substrates [8]. Figure 2d shows a region along the junction between the Ni-coated and bare YSZ surface, where a dremel was used to remove the Ni film.…”

“…However, the composite nature of Ni-YSZ anodes causes challenges, due to the unknown tpb length, the presence of distributed potentials, etc. Therefore, significant attention has been focused on impedance spectroscopy analysis of model thin film Ni anode structures (patterned anodes), where dense Ni films of controlled perimeter lengths are deposited on dense YSZ electrolytes in the form of regularly spaced strips [4][5][6][7][8][9][10], giving a simplified geometry and a well-controlled tpb length. Despite this, the results obtained from patterned electrode studies have been widely scattered.…”

Studying the CO–CO2 characteristics of SOFC anodes by means of patterned Ni anodes

“…The design of the pattern is composed of an area of 9.25 mm × 9.25 mm with parallel Ni stripes; in this study stripes with 25 m width, a spacing of 160 m and a thickness of 800 nm are chosen. In a previous study, this thickness has been found to ensure the stability of the structure during characteriza- tion at temperatures of up to 800 • C in reducing atmosphere [23]. An additional frame with 500 m width assures the contacting of all stripes, see Fig.…”

“…4. In our previous stability study we found that the Ni structure is subject to considerable temperature dependent morphological changes during the first 20 h of thermal exposure at 800 • C with consecutive stabilization [23]. Therefore, in order to assure a reproducible starting point for the characterization of patterned Ni anodes, the same standard initial heat treatment than for characterization in H 2 -H 2 O atmosphere has been applied prior to characterization in CO-CO 2 atmosphere (20 h at T = 800 • C, pH 2 = 8.6 × 10 4 Pa, pH 2 O = 1.5 × 10 4 Pa, pN 2 = 0 Pa).…”

Characteristics of SOFC Anode of Ni/YSZ Core-shell Manufactured Using sSpherical Ni and Nano YSZ Powders

“…또한 NiO가 Ni로 환원될 때 수반되는 부 피 변화에 의해 미세구조가 변화되는데 변화된 구조 는 재구축이 되지 않는다 4) . 외부적으로의 열화는 연 료로 공급되는 탄화수소계 연료에서의 carbon deposition으로 저온에서 metal dust 현상이 발생하여 구 조가 파괴되는 현상이 일어난다 [5][6] .…”