라니 니켈 촉매에 대한 알칼리형 연료전지용 수소극의 전극특성

이홍기; 이주성

Journal of the Korean Industrial and Engineering Chemistry, Vol.3, No.3, 527-534, September, 1992

Export Citation

라니 니켈 촉매에 대한 알칼리형 연료전지용 수소극의 전극특성

Hydrogen Electrode Performance with PTFE Bonded Raney Nickel Catalyst for Alkaline Fuel Cell

이홍기, 이주성

초록

Raney nickel 촉매를 이용하여 알칼리형 연료전지의 수소극을 제작하였다. 700℃에서 소결한 Raney nickel로 제작한 수소극의 경우 가장 좋은 전극성능을 갖는 450mA/cm²의 전류밀도를 나타냈으며 이때의 평균촉매입자 크기는 90Å이었다. CO- chemisorption 측정 및 분극곡선과 Tafel slope를 통하여 PTFE의 첨가량에 대한 전극의 전기화학적 성능을 고찰하였다. CO-chemisorption 측정 결과 5wt%의 PTFE가 첨가되었을 때 최고값을 갖는 것이 확인되었으나 전극에서의 전류밀도와 Tafel slope를 비교한 결과 10wt%의 PTFE를 첨가하는 경우가 가장 적당함을 알았다. Raney nickel제조시 nicke과 aluminum의 함량비는 60:40의 경우에 가장 좋은 전극 특성을 나타내었으며 담지량은 0.25g/cm²의 경우가 적당하였다. 전극제조시 촉매층의 press압 및 촉매층과 기체확산층과의 접합시의 Press압에 대한 영향도 검토하였다. 또한 촉매의 표면 구조를 SEM으로 관찰하였으며 활성화시간 및 열처리 온도 등 여러가지 조건에 대한 전극의 영향도 고찰하였다.

Raney nickel was used as catalyst in the hydrogen electrode for an alkaline fuel cell. The hydrogen electrode manufactured with the Raney nickel catalyst which was sintered at 700℃ was found to have the highest electrode performance. Using the Raney nickel powder of average particle size 90Å for the electrode, the current density which had been measured was 450mA/cm² at 80℃ using 6N KOH solution as an electrolyte. The effects of PTFE addition were investigated with CO- chemisorption, polarization curves and Tafel slope. CO-chemisorption had shown the optimum value when the Raney nickel was mixed with 5wt% of PTFE, but from the current density and Tafel slope at porous Raney nickel electrode, the appropriate value of PTFE addition was l0wt%. Recommendable Ni and Al portion for Raney nickel was 60 : 40 and loading amount was 0.25g/cm². Also the influence of pressing pressure for manufacturing catalytic layer and for junction with gas diffusion layer was examined. The morphology of catalyst surface was investigated with SEM. The influence of reactivation time and heat-treatment temperature were also studied.

[References]

Adams AA, Bacon FT, Wason RGH, "Fuel Cells," W. Mitchell, Jr., Academic Press, NY (1963)
Appleby AJ, Conway BE, Bockris JOM, "Electrocatalysis in Modern Aspects of Electrochemistry," Vol. 9, p. 369 (1974)
Appleby AJ, Foulikes FR, "Fuel Cell Handbook," Von Nostrand Reinhold, NY (1990)
Ewe H, Justi EW, Selbach HJ, Energy Conv. Manag., 24, 97 (1984)
Mund K, Richter G, vonStrum F, J. Electrochem. Soc., 124, 1 (1977)
Freel J, Pietres WJM, Abderson RB, J. Catal., 16, 281 (1970)
Despic AR, Diaz DM, Petrovic CB, Vujcic VL, J. Electrochem. Soc., 111, 1109 (1964)
Staples AB, Benforado DM, J. Korean Ind. Eng. Chem., 3(2), 189 (1992)
Kenjo T, Bull. Chem. Soc. Jpn., 54, 2553 (1981)
Kloinedinst KA, Vogel WM, Stonehart P, J. Mater. Sci., 12, 693 (1977)
Katan T, Bauman HF, J. Electrochem. Soc. Electrochem. Sci. Technol., 122, 77 (1975)
Tomida T, Nakabayashi I, J. Electrochem. Soc., 136, 3296 (1989)
Tracey UA, Powder Metallurgy, 2, 45 (1979)
Manon PG, "Chemical Industries," Vol. 15, Marcel Dekker, NY (1984)
Tomida T, Nakabayashi I, J. Electrochem. Soc., 136 (1989)
Jenseit W, Khalil A, Wendt H, Proceedings of the Fuel Cells, San Francisco, California, The Electrochemical Society (1989)
Appleby AJ, Foulkes FR, "Fuel Cell Handbook," Von Nostrand Reinhold, NY, p. 384 (1990)
Motoo S, Watanabe M, J. Electroanal. Chem., 160, 351 (1984)
Murray JL, Bennett LH, Baker H, "Binary Alloy Phase Diagram," American Society for Metals, Vol. 1, p. 142 (1986)

[1] Adams AA, Bacon FT, Wason RGH, "Fuel Cells," W. Mitchell, Jr., Academic Press, NY (1963)

[2] Appleby AJ, Conway BE, Bockris JOM, "Electrocatalysis in Modern Aspects of Electrochemistry," Vol. 9, p. 369 (1974)

[3] Appleby AJ, Foulikes FR, "Fuel Cell Handbook," Von Nostrand Reinhold, NY (1990)

[4] Ewe H, Justi EW, Selbach HJ, Energy Conv. Manag., 24, 97 (1984)

[5] Mund K, Richter G, vonStrum F, J. Electrochem. Soc., 124, 1 (1977)

[6] Freel J, Pietres WJM, Abderson RB, J. Catal., 16, 281 (1970)

[7] Despic AR, Diaz DM, Petrovic CB, Vujcic VL, J. Electrochem. Soc., 111, 1109 (1964)

[8] Staples AB, Benforado DM, J. Korean Ind. Eng. Chem., 3(2), 189 (1992)

[9] Kenjo T, Bull. Chem. Soc. Jpn., 54, 2553 (1981)

[10] Kloinedinst KA, Vogel WM, Stonehart P, J. Mater. Sci., 12, 693 (1977)

[11] Katan T, Bauman HF, J. Electrochem. Soc. Electrochem. Sci. Technol., 122, 77 (1975)

[12] Tomida T, Nakabayashi I, J. Electrochem. Soc., 136, 3296 (1989)

[13] Tracey UA, Powder Metallurgy, 2, 45 (1979)

[14] Manon PG, "Chemical Industries," Vol. 15, Marcel Dekker, NY (1984)

[15] Tomida T, Nakabayashi I, J. Electrochem. Soc., 136 (1989)

[16] Jenseit W, Khalil A, Wendt H, Proceedings of the Fuel Cells, San Francisco, California, The Electrochemical Society (1989)

[17] Appleby AJ, Foulkes FR, "Fuel Cell Handbook," Von Nostrand Reinhold, NY, p. 384 (1990)

[18] Motoo S, Watanabe M, J. Electroanal. Chem., 160, 351 (1984)

[19] Murray JL, Bennett LH, Baker H, "Binary Alloy Phase Diagram," American Society for Metals, Vol. 1, p. 142 (1986)