Solid oxide fuel cells with apatite-type lanthanum silicate-based electrolyte films deposited by radio frequency magnetron sputtering

摘要

In this study, solid oxide fuel cells (SOFCs) containing high-quality apatite-type magnesium doped lanthanum silicate-based electrolyte films (LSMO) deposited by RF magnetron sputtering are successfully fabricated. The LSMO film deposited at an Ar:O-2 ratio of 6:4 on an anode supported NiO/Sm0.2Ce0.8O2-delta (SDC) substrate followed by post-annealing at 1000 degrees C reveals a uniform and dense c-axis oriented polycrystalline structure, which is well adhered to the anode substrate. A composite SDC/La0.6Sr0.4Co0.2Fe0.8O3-delta cathode layer is subsequently screen-printed on the LSMO deposited anode substrate and fired. The SOFC fabricated with the LSMO film exhibits good mechanical integrity. The single cell with the LSMO layer of approximate to 2.8 mu m thickness reports a total cell resistance of 1.156 and 0.163 Omega cm(2), open circuit voltage of 1.051 and 0.982 V, and maximum power densities of 0.212 and 1.490 Wcm(-2) at measurement temperatures of 700 and 850 degrees C, respectively, which are comparable or superior to those of previously reported SOFCs with yttria stabilized zirconia electrolyte films. The results of the present study demonstrate the feasibility of deposition of high-quality LSMO films by RF magnetron sputtering on NiO-SDC anode substrates for the fabrication of SOFCs with good cell performance.