Silver (Ag) as anode and cathode current collectors in high temperature planar solid oxide fuel cells

Planar electrolyte supported solid oxide fuel cells were operated at 900 degrees C with humidified H-2 for 200 h using silver mesh and paste for cathode current collection. Continuous potentiostatic tests at 0.7 V appeared to induce migration of Ag towards electrode-electrolyte interphase, while continuous OCV tests caused no mass transport. Similar SOFCs fueled by coal syngas at 850 degrees C using Ag for both anode and cathode current collection indicated little, if any, Ag migration; providing the possibility of employing Ag for 100 h laboratory scale tests using coal-derived syngas. Use of high temperature steam, carbon dioxide and carbon monoxide did not result in the formation of silver carbonates. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.