Fabrication of Large-area Multi-scale-architectured Thin-Film SOFC via Commercially Viable Thin-film Technology

We have reported the ultimate performance level that the anode-supported solid oxide fuel cell (SOFC) can reach by employing thin-film electrolytes and nano-structure electrodes, without drastically changing the component materials. Based on the platform named as multi-scale-architectured thin-film SOFC (TF-SOFC), thin-film electrolytes of thickness less than 1 micron and electrodes with particle size in nm scale are successfully realized on NiO-YSZ anode supports, and a peak power density exceeding 500 mWcm^-2 at 500 ^oC is obtained.

Although this approach proves the potential of the thin-film technology to significantly improve the low-temperature performance of the SOFC, it is highly questionable that this platform can be transferred to the commercial sector because pulsed laser deposition (PLD) is employed to fabricate the cells. PLD is the best thin-film deposition research tool for the oxide with complex composition and has a high deposition rate, which is tremedous advantages for the thin film components in the TF-SOFC. Nevertheless, PLD has a small deposition area which cannot be larger than several cm by several cm in general, which is the most critical disadvantage of PLD to be employed as a commerciallization processing technique.

Therefore, to be employed in the commercial sector, it is the prerequisite that the multi-scale-architectured TF-SOFC should be realized by commercially viable techniques other than PLD. In this regard, the present study deals with the realization of the same platform by using other technique, specifically sputtering. Several key issues, such as nano-composite deposition, stoichiometry transfer, crystallinity of the thin films, etc., will be identified and the possible solutions to resolve these issues in sputtering will be suggested. A larger area (~ 5 cm by 5 cm) TF-SOFC using a 2-inch sputtering system will be fabricated to check the fesibility and its chracteristics will be compared with that of the cell fabricated using PLD.