Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5147781 | International Journal of Hydrogen Energy | 2017 | 7 Pages |
Abstract
Ni-Sn porous metals with different concentrations of Sn were prepared as potential current collectors for solid oxide fuel cells (SOFCs). The weight increase of these species was evaluated after heat-treatment under elevated temperatures in air for thousands of hours to evaluate the long-term oxidation resistance. Ni-Sn porous metals with 5-14 wt% of Sn exhibited excellent oxidation resistance at 600 °C, although oxidation became significant above 700 °C. Intermetallic Ni3Sn was formed at 600 °C due to phase transformation of the initially solid solutions of Sn in Ni in the porous metals. For the porous metal with 10 wt% of Sn, the oxidation rate constant at 600 °C in air was estimated to be 8.5 Ã 10â14 g2 cmâ4 sâ1 and the electrical resistivity at 600 °C was almost constant at approximately 0.02 Ω cm2 up to an elapsed time of 1000 h. In addition, the gas diffusibility and the power-collecting ability of the porous metal were equivalent to those of a platinum mesh when applied in the cathode current collector of a SOFC operated at 600 °C. Ni-Sn porous metals with adequate contents of Sn are believed to be promising cathode current collector materials for SOFCs for operation at temperatures below 600 °C.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Chihiro Hiraiwa, Hiromasa Tawarayama, Hajime Ota, Takahiro Higashino, Kazuki Okuno, Masatoshi Majima,