Cell configuration
Schematic diagram of the cell configuration and reactor system used in the thermally self-sustaining micro-SOFC.
(a) The disc-shaped fuel cell comprises an SDC (samaria-doped ceria) electrolyte (about 20 microns thick) supported on a nickel plus SDC anode (0.7 mm) with BSCF (barium strontium cobalt iron oxide) plus SDC (70:30wt%) as the cathode (5–10 microns);
a 10-micron-thick ruthenium and cerium oxide catalyst layer was coated onto the entire anode
surface, with the exception of about 0.2 cm2 at the centre, over which the current collector (silver paste) was placed; the entire cathode surface was
covered with a layer of BSCF plus silver which served as the current collector (20–30 microns).
(b) The fuel-cell reactor comprises a removable ceramic thermal insulator or blanket, an inner quartz tube, and an outer quartz tube for introducing the gas mixture for the fuel cell. Component dimensions (L, width; ID, inner diameter; OD, outer diameter) are as indicated (image and text: Nature 435 795).