Review on microfabricated micro-solid oxide fuel cell membranes

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.…”

“…The area of the measured membranes is 2.8 mm 2 for a total active area of 2 mm 2 , which represents an enhancement of ca. 20x over previously reported basic free-standing membrane configurations [3]. The mechanical stability of the M A N U S C R I P T…”

“…In this sense, the here-presented results suggest the need of temperatures higher than 650ºC for having a good performance of the LSC/YSZ interface (dot line in Figure 8). Although this fact forces to work at higher temperatures than those previously published µSOFC devices based on Pt/YSZ/Pt (350-550ºC, [3,13]), the proven stability of the LSC films at such temperatures makes the system more reliable considering the fast degradation observed for pure metallic based devices. Moreover, working at such high temperatures allows substantially increasing the electrolyte thickness to several hundreds of nm.…”

“…The micro SOFC (µSOFC) concept is based on the development of ultrathin electrolytes supported on low thermal mass structures [3][4][5][6][7][8][9]. This combination keeps the main benefits of SOFC technology, i.e.…”

“…maximizing the membrane active area while ensuring structural and thermomechanical stability, in order to enlarge the total power achievable per single device. Opposed to original simple squared membrane designs with a limited maximum size [3], recent works focus on the fabrication of membranes with enlarged areas reaching several mm 2 . First Rey-Mermet et al [10] and lately Ramanathan et al [4] used dense Ni grids as robust support for fabricating membranes with a maximum area of 25 mm 2 .…”