Thermal stabilities of nanoporous metallic electrodes at elevated temperatures

Porous La0.6Sr0.4CoO3−δ thin film cathodes for large area micro solid oxide fuel cell power generators

“…YSZ membranes present thermo-mechanical stability through the whole intermediate temperature range (up to 700ºC), and reach the target value usually established for the Area Specific Resistance (ASR=0.15 Ωcm 2 , [11]) at temperatures as low as 400ºC [6,12]. However, despite the good performance achieved by the thin electrolytes themselves and the promising works reported on µSOFC devices (a maximum power density of 1037 mW/cm 2 was reported by Kerman et al [13]), the quick degradation shown by the typically implemented metallic electrodes [3,14] at operating temperatures still hinders the way to the commercialization of µSOFC devices [15][16][17]. A difficult balance between two opposite phenomena is required for the development of reliable metallic-based thin film electrodes, namely: (i) the promotion of thin film dewetting with temperature, in order to form a porous film and enlarge the triple phase boundary (TPB) length without losing the connectivity; (ii) the limitation of the dewetting process that makes the thin films unstable at operating temperatures.…”

Direct Applicability of La0.6Sr0.4CoO3 – δ Thin Film Cathode to Yttria Stabilised Zirconia Electrolytes at T ≤ 650 °C

“…LSC films were deposited at room temperature then post-annealed to develop a porous structure. This low temperature deposition and post-annealing is a frequently used approach to obtain a porous structure in using thin film deposition techniques [11,[18][19][20]. Post-annealing temperatures and oxygen ambient pressures during deposition were varied to optimise physical properties such as the crystallinity and the microstructure of the film.…”

Micro-solid oxide fuel cells: status, challenges, and chances

“…The anode thin films are deposited on an insulating micro-SOFC substrate, such as Foturan Ò or silicon wafers coated with a silicon nitride (Si 3 N 4 ) or silicon dioxide (SiO 2 ) insulating layer. It is known that metallic films, deposited on insulating substrates via MEMS techniques, are in a metastable state and suffer degradation of microstructure over time at elevated temperatures due to Ostwald ripening [52][53][54][55]. The degree of porosity is a function of the thickness and the annealing of the thin films [56].…”

“…Further materials have been investigated for micro-SOFC anodes: platinum-nickel alloys [55], metallic nickel [28,30], as well as Ni-YSZ [57], and Ni-CGO [58] cermets in which the electronically conducting nickel forms a pathway for electrons, and the ionically conducting YSZ ceramic network prevents excessive nickel grain growth.…”