Traditional seals for planar solid oxide fuel cells (pSOFCs) are rigid glass and glass-ceramic, which have caused the problem of being unable to replace malfunctioning components. Non-glass sealants have become a recent trend. In this paper, fumed silica-infiltrated alumina-silica fiber paper gaskets were investigated as a novel compressive seal for planar solid oxide fuel cells. The leak rates decreased with increase of the silica-infiltration amount and the compressive load. Samples pre-stressed at 10 MPa indicated far superior sealing characteristics, with leak rates as low as 0.04 seem cm(-1) at a I MPa compressive stress and a 10 kPa pressure gradient, and 0.05 seem cm(-1) for 0.05 MPa, and a 1.4 kPa pressure gradient. (c) 2006 Elsevier B.V. All rights reserved.