알칼리형 연료전지에서 산소환원에 미치는 촉매 특성 연구 I.La0.6Sr0.4Co1-xFexO3의 합성과 산소환원반응

문형대; 이호인

Journal of the Korean Industrial and Engineering Chemistry, Vol.7, No.3, 543-553, June, 1996

A Study on the Catalytic Characteristics of Oxygen Reduction in an Alkaline Fuel Cell - I. Synthesis of La_0.6 Sr_0.4 Co_1-xFe_xO₃ and Reduction Reaction of Oxygen

문형대, 이호인

초록

산소전극 촉매로서 페롭스카이트형 산화물을 사용하여 알칼리형 연료전지에서의 산소환원반응에 관하여 연구하였다 능금산(malic acid)을 사용하여 고표면적의 페롭스카이트형 La_0.6 Sr_0.4 Co_1-xFe_xO₃(x = 0.00, 0.01, 0.10, 0.20, 0.35 및 0.50) 산화물을 제조하였으며, Fe 치환량과 암모니아수 첨가량에 따른 XRD 구조와 비표면적의 변화를 고찰하여 Fe와 암모니아간에 생성되어지는 착화합물이 페롭스카이트로의 구조안정화와 비표면적 증대의 주요임을 알았다. 그리고 페롭스카이트 단일상을 얻기 위해서는 다단계 승온처리가 필요했으며, XRD 실험결과 단순 정입방체상이 형성됨을 확인하였다. La_0.6 Sr_0.4 Co_1-xFe_xO₃ 산화물을 촉매로 사용한 알칼리형 연료전지용 산소전극의 산소환원반응활성을 측정하기 위하여 순환 전압-전류법, 정전압-전류법, 전류단절법 등을 이용하였다. La_0.6 Sr_0.4 Co_1-xFe_xO₃ 산화물에서 Fe의 치환비가 증가함에 따라, x=0.01에서 최소, x=0.20와 0.35 사이에서 최대의 산소환원활성(전류밀도)을 보였으며, 이와 같은 경향은 표면적의 변화와 무관하였다.

Oxygen reduction in an alkaline fuel cell was studied by using perovskite type oxides as an oxygen electrode catalyst. The high surface area catalysts were prepared by malic acid method and had a formula of La_0.6 Sr_0.4 Co_1-xFe_xO₃(x=0.00, 0.01, 0.10, 0.20, 0.35 and 0.50). From the result of XRD pattern and specific surface area due to the amount of Fe substitution and the consumption of ammonia-water, the complex formation of Fe ion with NH₃ was the main factor for both the phase stability of perovskite and the increase of specific surface area. Multi-step calcination was necessary to give a single phase of perovskite in catalyst precursor. The crystal structure of the catalysts was simple cubic perovskite, which was verified from the XRD patterns of the catalysts. The activity of oxygen reduction was monitored by the techniques of cyclic voltammetry, static voltage-current method, and current interruption method. The activity(current density) of oxygen reduction showed its minimum at x=0.01 and its maximum between 0.20 and 0.35 of x-value in La_0.6 Sr_0.4 Co_1-xFe_xO₃ oxide. This tendency was independent of the change of surface area.

[References]

Zhang H, Teraoka Y, Yamazoe N, Chem. Lett., 665 (1987)
Anderton DJ, Sale FR, Powder Metall., 22, 14 (1979)
Baythoun MSG, Sale FR, J. Mater. Sci., 17, 2757 (1982)
Teraoka Y, kakebayashi H, Moriguchi I, Kagawa S, Chem. Lett., 673 (1991)
Libby WF, Science, 171, 489 (1971)
Nitadori T, Misono M, J. Catal., 93, 459 (1985)
Zhang H, Teraoka Y, Yamazoe N, Appl. Catal., 41, 137 (1988)
Meadowcroft DB, Nature, 226, 847 (1970)
Sakaguchi M, Uematsu K, Sakata A, Sato M, Electrochim. Acta, 35, 65 (1990)
Tamura H, Yonegama H, Matsmoto Y, "Electrodes of Conductive Metallic Oxides, Part A," S. Trasatti, Ed., Elsevier Science Publishing Company, Amsterdam (1980)
Matsumoto Y, Yamada S, Nishida T, Sato E, J. Electrochem. Soc., 127, 2360 (1980)
Nitadori T, Misono M, Bull. Chem. Soc. Jpn., 61, 621 (1988)
Obayashi H, Kudo T, Denki Kagaku, 44, 503 (1976)
Kojima I, Adachi H, Yasumori I, Surf. Sci., 130, 50 (1983)
Salyama T, Yamazoe N, Eguchi K, Ind. Eng. Chem. Prod. Res. Dev., 24, 19 (1985)
Mizusaki J, Mima Y, Yamauchi S, Fueki K, J. Solid State Chem., 80, 102 (1989)
Sekido S, Tachilbana H, Yamamura Y, Kambara T, Solid State Ion., 37, 253 (1990)
Devi P, Rao M, J. Solid State Chem., 98, 237 (1992)
Mizusaki J, Yoshihiro M, Yamauchi S, Fueki K, J. Solid State Chem., 67, 128 (1987)
Kudo T, Obayashi H, Yoshida M, J. Electrochem. Soc., 124, 321 (1977)
Butler IS, Harrod JF, "Inorganic Chemistry," The Benjamin/Cummings Publishing Company, Inc. (1989)
Shimizu Y, Uemura K, Miura N, Yamazoe N, Chem. Lett., 1979 (1988)
Miura N, Shimizu Y, Yamazoe N, 일화, 751 (1986)
Wadsley AD, "New Stoichiometric Compounds," L. Mandeleorn, Ed., p. 134, Academic Press, New York/London (1964)
Wu Y, Yu T, Wang C, Xie X, Yu Z, Fan X, Fan Z, Wang L, J. Catal., 120, 88 (1989)
Zhang HM, Shimizu Y, Teraoka Y, Miura N, Yamazoe N, J. Catal., 121, 432 (1990)
Yeung KLK, Tseung ACC, J. Electrochem. Soc., 125, 878 (1978)
Wattiaux A, Grenier JC, Pouchard M, Hagenmuller P, J. Electrochem. Soc., 134, 1714 (1987)
Kudo T, Obayashi H, Jejo T, J. Electrochem. Soc., 122, 159 (1975)
Matsumoto Y, Yamada S, Nishida T, Sato E, J. Electrochem. Soc., 127, 2360 (1980)
Shimizu Y, Uemura K, Matsuda H, Miura N, Yamazoe N, J. Electrochem. Soc., 137, 3430 (1990)
Shimizu Y, Matsuda H, Miura N, Yamazoe N, Chem. Lett., 1033 (1992)
Teraoka Y, Fukuda H, Kagawa S, Chem. Lett., 1 (1990)

[1] Zhang H, Teraoka Y, Yamazoe N, Chem. Lett., 665 (1987)

[2] Anderton DJ, Sale FR, Powder Metall., 22, 14 (1979)

[3] Baythoun MSG, Sale FR, J. Mater. Sci., 17, 2757 (1982)

[4] Teraoka Y, kakebayashi H, Moriguchi I, Kagawa S, Chem. Lett., 673 (1991)

[5] Libby WF, Science, 171, 489 (1971)

[6] Nitadori T, Misono M, J. Catal., 93, 459 (1985)

[7] Zhang H, Teraoka Y, Yamazoe N, Appl. Catal., 41, 137 (1988)

[8] Meadowcroft DB, Nature, 226, 847 (1970)

[9] Sakaguchi M, Uematsu K, Sakata A, Sato M, Electrochim. Acta, 35, 65 (1990)

[10] Tamura H, Yonegama H, Matsmoto Y, "Electrodes of Conductive Metallic Oxides, Part A," S. Trasatti, Ed., Elsevier Science Publishing Company, Amsterdam (1980)

[11] Matsumoto Y, Yamada S, Nishida T, Sato E, J. Electrochem. Soc., 127, 2360 (1980)

[12] Nitadori T, Misono M, Bull. Chem. Soc. Jpn., 61, 621 (1988)

[13] Obayashi H, Kudo T, Denki Kagaku, 44, 503 (1976)

[14] Kojima I, Adachi H, Yasumori I, Surf. Sci., 130, 50 (1983)

[15] Salyama T, Yamazoe N, Eguchi K, Ind. Eng. Chem. Prod. Res. Dev., 24, 19 (1985)

[16] Mizusaki J, Mima Y, Yamauchi S, Fueki K, J. Solid State Chem., 80, 102 (1989)

[17] Sekido S, Tachilbana H, Yamamura Y, Kambara T, Solid State Ion., 37, 253 (1990)

[18] Devi P, Rao M, J. Solid State Chem., 98, 237 (1992)

[19] Mizusaki J, Yoshihiro M, Yamauchi S, Fueki K, J. Solid State Chem., 67, 128 (1987)

[20] Kudo T, Obayashi H, Yoshida M, J. Electrochem. Soc., 124, 321 (1977)

[21] Butler IS, Harrod JF, "Inorganic Chemistry," The Benjamin/Cummings Publishing Company, Inc. (1989)

[22] Shimizu Y, Uemura K, Miura N, Yamazoe N, Chem. Lett., 1979 (1988)

[23] Miura N, Shimizu Y, Yamazoe N, 일화, 751 (1986)

[24] Wadsley AD, "New Stoichiometric Compounds," L. Mandeleorn, Ed., p. 134, Academic Press, New York/London (1964)

[25] Wu Y, Yu T, Wang C, Xie X, Yu Z, Fan X, Fan Z, Wang L, J. Catal., 120, 88 (1989)

[26] Zhang HM, Shimizu Y, Teraoka Y, Miura N, Yamazoe N, J. Catal., 121, 432 (1990)

[27] Yeung KLK, Tseung ACC, J. Electrochem. Soc., 125, 878 (1978)

[28] Wattiaux A, Grenier JC, Pouchard M, Hagenmuller P, J. Electrochem. Soc., 134, 1714 (1987)

[29] Kudo T, Obayashi H, Jejo T, J. Electrochem. Soc., 122, 159 (1975)

[30] Matsumoto Y, Yamada S, Nishida T, Sato E, J. Electrochem. Soc., 127, 2360 (1980)

[31] Shimizu Y, Uemura K, Matsuda H, Miura N, Yamazoe N, J. Electrochem. Soc., 137, 3430 (1990)

[32] Shimizu Y, Matsuda H, Miura N, Yamazoe N, Chem. Lett., 1033 (1992)

[33] Teraoka Y, Fukuda H, Kagawa S, Chem. Lett., 1 (1990)