Abstract
We examine the degree to which sulfur-based fuel contaminants, such as hydrogen sulfide (H2S), can adsorb on the molybdenum sulfide-based anode of a solid oxide fuel cell (SOFC) under normal SOFC conditions. Our examination takes into account multiple adsorption/desorption events involving H2S and the fuel (H-2). By means of a kinetic model that allows us to approximate the rate of adsorbed oxygen formation based on experimental O2- anion consumption at the triple-phase-boundary (TPB), we also consider the reaction mechanisms associated with the formation and desorption of H2O(g), SO2(g), and S-2(g). Preferred adsorption sites. energies, transition states, and kinetic barriers are calculated for the resulting species, SHx, OHx, SOx, and S-2 (x = 0-2). We have concluded that at typical SOFC operating conditions, the level of adsorbed sulfur on the MoS2 anode surface will not exceed 25% (one S surface atom for every one Mo surface atom).
Original language | English |
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Pages (from-to) | 193 - 203 |
Number of pages | 10 |
Journal | Journal of Physical Chemistry C |
Issue number | 113 |
DOIs | |
Publication status | Published - 1 Mar 2009 |
Keywords
- solid oxide fuel cell