TY - GEN
T1 - Effects of activity and deactivation of NiYSZ SOFC anodes on thermal profiles during internal reforming of methane
AU - Strohm, James J.
AU - King, David L.
AU - Wang, Xianqin
AU - Singh, Prabhakar
AU - Recknagle, Kurt
AU - Wang, Yong
PY - 2007
Y1 - 2007
N2 - One of the advantages of internal reforming is improved thermal management by directly coupling the exothermic electrochemical oxidation with the endothermic steam reforming of hydrocarbons. Significant differences in the rates of oxidation and reforming can lead to the development of thermal gradients across the anode plate that can compromise the physical integrity of the cell. The purpose of this study is to directly measure the thermal gradient created during internal reforming of methane with relation to the inherent activity and deactivation behavior of NiYSZ anodes. The current study shows that the endotherm will migrate down the anode plate until a stable thermal profile is achieved. This migration can be related to the sintering behavior of both bulk-Ni and Ni crystallites (evolved from the YSZ). During testing of an anode plate, steam and hydrogen treatments are not sufficient to fully stabilize the activity of the NiYSZ by sintering. Evidence from thermal profiles, activity testing, Ni surface area analysis, and TEM imaging suggests that methane reforming may have a significant role in the evolution and subsequent sintering of Ni crystallites leading to a stable structure.
AB - One of the advantages of internal reforming is improved thermal management by directly coupling the exothermic electrochemical oxidation with the endothermic steam reforming of hydrocarbons. Significant differences in the rates of oxidation and reforming can lead to the development of thermal gradients across the anode plate that can compromise the physical integrity of the cell. The purpose of this study is to directly measure the thermal gradient created during internal reforming of methane with relation to the inherent activity and deactivation behavior of NiYSZ anodes. The current study shows that the endotherm will migrate down the anode plate until a stable thermal profile is achieved. This migration can be related to the sintering behavior of both bulk-Ni and Ni crystallites (evolved from the YSZ). During testing of an anode plate, steam and hydrogen treatments are not sufficient to fully stabilize the activity of the NiYSZ by sintering. Evidence from thermal profiles, activity testing, Ni surface area analysis, and TEM imaging suggests that methane reforming may have a significant role in the evolution and subsequent sintering of Ni crystallites leading to a stable structure.
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M3 - Conference contribution
AN - SCOPUS:37349052172
SN - 0841269556
SN - 9780841269552
T3 - ACS National Meeting Book of Abstracts
BT - 234th ACS National Meeting, Abstracts of Scientific Papers
T2 - 234th ACS National Meeting
Y2 - 19 August 2007 through 23 August 2007
ER -