In the present study, the C3H8 decomposition reaction is studied in a double-chamber proton-conducting cell-reactor. The proton conductor was a strontia-ceria-ytterbia perovskite disk of the form: SrCe0.95Yb0.05O3-alpha. The working electrode-catalyst was either Pt or Pd, in the form of a polycrystalline film. The reaction temperature varied between 923 and 1023 K and the partial pressure of propane in the feed gas was 2 kPa. The hydrogen produced by the reaction was electrochemically transported through the walls of the proton-conducting disk, to the outer reactor-chamber. The two electrodes (Pt and Pd) are compared in terms of their catalytic and electrocatalytic activities. (c) 2005 Elsevier B.V. All rights reserved.