DOI QR코드

DOI QR Code

Fabrication of an Electrochemical Cell using a Lanthanum Stannate Pyrochlore Catalyst and its Characterization of NOx Gas Decomposition

Lanthanum Stannate Pyrochlore 촉매를 이용한 전기화학 촉매 셀의 제조 및 NOx 분해 특성 분석

  • Park, Saro-Han (Department of Ceramic Engineering, Yonsei University) ;
  • Moon, Joo-Ho (Department of Ceramic Engineering, Yonsei University)
  • Published : 2002.01.01

Abstract

Electrochemical cells for decomposing $NO_x$ were fabricated using a hydrothermally synthesized lanthanum stannate pyrochlore catalyst. Thick film of the catalyst on the YSZ electrolyte disk was produced by screen-printing a paste consisted of $La_2Sn_2O_7$ and YSZ powders. Direct current was applied to the electrochemical cell to promote an electrochemical catalytic decomposition of $NO_x$. $NO_x$ decomposition behavior of the rectant gas mixture ($NO_x$ 0.1%, $O_2$ 2%) was investigated at 700${\circ}C$ under atmosphere pressure using on-line gas chromatography and $NO_x$ analyzer. It was observed that microstructure of the catalyst layer significantly influences the electrocatalystic decomposition of $NO_x$.

Lanthanum Stannate Pyrochlore($La_2Sn_2O_7$) 촉매를 이용하여 $NO_x$ 제거를 위한 전기화학 촉매 셀을 제조하였다. 촉매전극은 수열합성법을 통해 합성한 $La_2Sn_2O_7$ 분말과 안정화 지르코니아(YSZ) 분말을 혼합하여 촉매층 페이스트를 제조한 후 이를 YSZ 디스크 고체전해질 위에 스크린프린팅하여 후막을 도포하였다. 위와 같이 제조한 전기화학 셀의 $NO_x$ 분해 실험은 galvanostat을 이용하여 셀에 일정한 전류를 인가하고 700${\circ}C$에서 NO 0.1%와 산소 2%의 반응가스에 대한 분해 정도를 gas chromatography와 NOx analyzer를 이용하여 측정을 하였다. 촉매 전극의 두께와 소성 온도에 따른 촉매전극의 미세구조가 $NO_x$ 분해에 미치는 영향과 전류량(0.05∼0.6A)에 따른 $NO_x$ 분해율을 측정하였다.

Keywords

References

  1. S. Bhattacharyya and R. K. Das, 'Catalytic Reduction of NO$_x$ in Gasoline Engine Exhaust over copper and Nikelexchanged X zeolite Catalysts,' Energ. Convers. Manage., 42 2019-27 (2001) https://doi.org/10.1016/S0196-8904(01)00059-0
  2. R. M. Heck and R. J. Farranto, 'Automobile Exhaust Catalysts,' Appl. Catal. A Gel., 221 443-57 (2001) https://doi.org/10.1016/S0926-860X(01)00818-3
  3. S. Bredikhin, K. Maeda and M. Awano, 'NO Decomposition by an Electrochemical Cell with mixed Oxide Working Electrode,' Solid State lonics, 144 1-9 (2001) https://doi.org/10.1016/S0167-2738(01)00862-1
  4. H. Hwang, J. Moon, K. Matsuda, M. Awano and K. Maeda, 'Design of Multi-layered Electrochemical Cell for Exhaust Gas Purificadon,' J. Ceram. Soc. Jpn., 110 [5] 465-71 (2002) https://doi.org/10.2109/jcersj.110.465
  5. T. Hibino, T. Inoue and M. Sano, 'Electrochemical Reduction of NO by Altemating Current Electrolysis using Yttriastabilized Zirconia as the Solid Electrolyte,' Solid State lonics, 130 19-29 (2000) https://doi.org/10.1016/S0167-2738(00)00581-6
  6. C. G. Vayenas and S. I. Bebelis, 'Electrochemical Promotion,' Solid State lonics, 94 267-77 (1997) https://doi.org/10.1016/S0167-2738(96)00511-5
  7. C. Tofon, D. Klvana and J. Kirchnerova, 'Direct Decomposition of Nitric Oxide over Perovskite type Catalysts,' Appl. Catal. A Ger., 226 225-40 (2002) https://doi.org/10.1016/S0926-860X(01)00908-5
  8. Y. Teraoka, K. Toiigoshi, H. Yamaguchi, T. Dceda and S. Kagawa, 'Direct Decomposition of Nitric Oxide over Stannate Pyrochlre Oxides : Relationship between Solid state Chemistry and Catalytic Activity,' J. Mol. Catat. A Chem., 155 73-80 (2000) https://doi.org/10.1016/S1381-1169(99)00320-9
  9. J. Moon, M. Awano and K. Maeda, 'Hydrothermal Synthesis and Formation Mechanisms of Lanthanum Tin Pyrochlore Oxide,' J. Am. Ceram. Soc., 84 [11] 2531-6 (2001) https://doi.org/10.1111/j.1151-2916.2001.tb01048.x
  10. J. Heo, D. Lee, J. Lee, J. Kim, J. Kim, H. Lee and J. Moon, 'Effect of the Pore Stmcture on the Anodic Property of SOFC,' J. Kor. Ceram. Soc., 39 [1] 86-91 (2002) https://doi.org/10.4191/KCERS.2002.39.1.086