Surface Fractals and Wetting Properties of Porous Anodes Strengthened by Ni₃Al for Molten Carbonate Fuel Cell

Abstract:

The contact angles of pure Ni, Ni/7wt%Ni3Al, Ni/5wt%Ni3Al/ 5wt%Cr and Ni/10wt%Cr anodes for the MCFC were measured by means of the capillary rise method in 62mol%Li2CO3+ 38mol%K2CO3 and 52mol%Li2CO3+ 48mol% Na2CO3 electrolyte and at different atmosphere. Also surface fractal dimension (Ds), which could characterize pore structure of the anodes, was calculated from experimental data obtained by mercury porosimetry and nitrogen adsorption method. The surface fractal dimensions of the anode were in range from 2.75 to 2.81, because porosities of the anodes for MCFC were controlled regularly to about 62% during sintering. It was investigated from wetting-in experiment by capillary-rise method that the contact angles between the anodes and the carbonate electrolytes were relatively decreased at CO2 atmosphere rather than air atmosphere and the angles were also decreased in the 62mol%Li2CO3+38mol%K2CO3 electrolyte rather than that measured and in the 52mol%Li2CO3+48mol% Na2CO3 electrolyte.

• Periodical: Advanced Materials Research (Volumes 26-28)
• Pages: 861-864
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.26-28.861
• Online since: October 2007
• Authors: Yun Sung Kim, Kil Ho Moon, Jun Heok Lim
• Keywords: Contact Angle (CA), Creep, Molten Carbonate Fuel Cell, Porous Anode, Wetting

References

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[20] 40 60 80 100 1E-6 1E-5 1E-4 1E-3 (a) Pure Ni anode 13. 78X102 kPa 6. 89X102 kPa 3. 45X102 kPa Creep rate (s -1 ).

[20] 40 60 80 100 1E-6 1E-5 1E-4 1E-3 (b) Ni/7wt%Ni3Al anode 13. 78X10.

[2] kPa 6. 89X102 kPa 3. 45*102 kPa Creep rate (s -1 ) Fig. 3. Creep rate curves for the anodes under different applied loads at 650°C.

[1] 0 0.

[1] E -6.

[1] E -5.

[1] E -4.

[1] E -3.

[6] . 8 9 (a ) n = 1 . 3 n = 1 . 3 n = 1 . 3 n = 1 . 3 n = 0 . 5 1.

[1] 3 . 7 8.

[3] . 4 5.

[2] h r.

[8] h r.

[2] 8 . 5 h r.

[6] 0 h r.

[1] 0 0 h r Creep rate (s -1 ).

[1] 0 0.

[1] E - 6.

[1] E - 5.

[1] E - 4.

[1] E - 3.

[6] . 8 9 (b ) n = 0 . 4 6 n = 0 . 4 8 n = 0 . 5 n = 0 . 7 n = 2 . 1.

[1] 3 . 7 8.

[3] . 4 5.

[2] h r.

[8] h r.

[2] 8 . 5 h r.

[6] 0 h r.

[1] 0 0 h r Creep rate (s -1 ) Fig. 4. Creep exponents of (a) pure Ni, (b) Ni/7wt%Ni3Al anodes.