Silver Nanomesh as a Cathode for Solid Oxide Fuel Cells

Abstract

We have tested a silver nano-mesh with close-packed holes as cathodic catalysts for intermediate temperature solid oxide fuel cells. The nano-mesh structure was fabricated in a close-packed hexagonal array with the pore size of 500~600 nm. Fuel cell tests were conducted using the nano-mesh silver cathodes with commercial 100 ȝm-thick 8% yttria stabilized zirconia electrolytes and sputtered porous platinum anodes. Performance of the fuel cells was analyzed by the current-voltage and the potentiostatic current measurements at temperatures of 250~300ºC. We confirmed that the nano-mesh silver cathodes improved fuel cell performance dramatically and enhanced stability against thermal degradation and morphological agglomeration compared to randomly sputtered porous silver cathodes.

(Invited) Atomic Layer Deposited Yttria Stabilized Zirconia Barrier Layer for Proton Conducting Oxide

“…Nanoscale yttria stabilized zirconia (YSZ) films were fabricated using ALD by sequential deposition of its component oxides (ZrO 2 + Y 2 O 3 ) using metalorganic precursors described elsewhere (6). YSZ films were also deposited by pulsed laser deposition (PLD) to study the effects of fabrication methods on proton transport properties.…”

Application of silver in microtubular solid oxide fuel cells

“…Then the voltage was set to 0.7 V (potentiostatic mode) and a short 1 h constant voltage test was performed. Afterwards, the fuel was changed to a mixture of CH 4 :air (dry air) with molar ratio CH 4 :air of 1:2.4 and a long-term durability test was conducted at 0.7 V (CH 4 48 ml min −1 ). These conditions were chosen to simulate the realistic conditions of a µSOFC auxiliary power unit (APU) [27].…”

“…For the cells tested for more than 850 h, not only the degradation of the silver sealing layer (Ag paste) was observed, but additionally, a significant disintegration of the silver current collecting wire fastened to the anode. The cell with the CPOX catalyst was fed with the mixture of CH 4 and air in the molar ratio 1:2.4. Approximately, 70% of the fuel was converted on the catalyst before it reached the anode [28].…”

“…The presence of silver will also act as a catalyst for oxygen reduction [3]. Silver has been proven as a cathode material showing good results at intermediate temperatures in SOFC [1,[4][5][6]. In these tests, the limiting feature was the length of the oxygen diffusion paths.…”