TY - GEN
T1 - Theoretical investigations of solid oxide fuel cell anode materials
AU - Botte, Gerardine G.
AU - Marquez, Andres I.
PY - 2005
Y1 - 2005
N2 - The interactions of H2 and H2S with a commercially available anode material for SOFC were studied to provide a better understanding of the degradation of the material in the presence of H2S. From the MD simulations in an H2S/H2 environment at 850°C, the RDF Ni-H peak was smaller than the one without H2S and was closer than the Ni-S pair case, indicating that the H2S is less attracted to the surface than hydrogen and the hydrogen moves slower in the presence of H2S, in agreement with the quantum chemistry results. The H2S oxidation could start taking place but at a slower rate than H2 oxidation (mass transport limitations are important). The diffusion coefficients of H2 in gas phase close to the surface of the electrode increased when increasing temperature, where values in the order of 10-7 sq cm/sec, 10-6 sq cm/sec, and 1.35 × 10-4 sq cm/sec for 25°, 600°, and 850°C, respectively, were found. When H2S was present in the mixture, the diffusivity of hydrogen was about 1.10 × 10-4 sq cm/sec at 850°C (20% lower than for H2 alone). This is an abstract of a paper presented at the AIChE Annual Meeting and Fall Showcase (Cincinnati, OH 1/04/2005).
AB - The interactions of H2 and H2S with a commercially available anode material for SOFC were studied to provide a better understanding of the degradation of the material in the presence of H2S. From the MD simulations in an H2S/H2 environment at 850°C, the RDF Ni-H peak was smaller than the one without H2S and was closer than the Ni-S pair case, indicating that the H2S is less attracted to the surface than hydrogen and the hydrogen moves slower in the presence of H2S, in agreement with the quantum chemistry results. The H2S oxidation could start taking place but at a slower rate than H2 oxidation (mass transport limitations are important). The diffusion coefficients of H2 in gas phase close to the surface of the electrode increased when increasing temperature, where values in the order of 10-7 sq cm/sec, 10-6 sq cm/sec, and 1.35 × 10-4 sq cm/sec for 25°, 600°, and 850°C, respectively, were found. When H2S was present in the mixture, the diffusivity of hydrogen was about 1.10 × 10-4 sq cm/sec at 850°C (20% lower than for H2 alone). This is an abstract of a paper presented at the AIChE Annual Meeting and Fall Showcase (Cincinnati, OH 1/04/2005).
KW - HS/H interactions
KW - HS/H solid diffusion coefficients
KW - Molecular dynamics
KW - Quantum chemistry investigations
KW - Solid Oxide Fuel Cells
KW - Sulfur tolerant anode
UR - http://www.scopus.com/inward/record.url?scp=33646771399&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:33646771399
SN - 0816909962
SN - 9780816909964
T3 - AIChE Annual Meeting Conference Proceedings
BT - 05AIChE
PB - American Institute of Chemical Engineers
Y2 - 30 October 2005 through 4 November 2005
ER -