Single-cell solid oxide fuel cell (SOFC) experiments using Ni yttria-stabilized zironia (YSZ) and Co-YSZ anodes were performed to examine the electrochemical oxidation of H-2 and H2S/H-2 mixtures. The introduction of 10%v/v H2S into the fuel stream resulted in anodes that initially showed significant signs of degradation. However, when all of the metal was changed to metal-sulfide, the performance was enhanced under most tested conditions, suggesting that metal-sulfides are viable anode materials for SOFC systems. Electrochemical experiments, mass spectrometry of the exhaust gas, and X-ray diffraction of the postrun anodes show that the main anodic reaction is hydrogen oxidation in both fuel streams. Direct current experiments at various temperatures were performed to determine the inverse Tafel slope (Lefat slope, b(-1)) and the resulting charge-transfer coefficients for Ni-, Co-, NiS- and CoS-YSZ anodes. For three of the four anodes tested, the Lefat slope decreased with increasing T but not with the required slope of alpha F/R. The relationship was better represented by alpha F/R + K. The charge-transfer coefficient was determined to be 1.5 for Ni-, Co- and NiS-YSZ anodes, suggesting that the rate-determining step of hydrogen oxidation on these anodes is the electron transfer between Had and O2-. The CoS-YSZ exhibited traditional Tafel behavior such that a remained constant over a wide temperature range but yielded a charge-transfer coefficient much less than that of the other anodes (alpha = 0.21 +/-0.04).