Journal of the Korean Chemical Society (대한화학회지)

Korean Chemical Society (대한화학회)
권호 표지

Electrode Kinetics for Mixed Ligand Complexes of Cobalt (III) with Bis (ethylenediamine) and Monodendate Ligands

한자리 배위자와 에틸렌디아민의 코발트 (III) 착물에 대한 전극반응 속도론

  • Jung-Ui Hwang (Department of Chemistry, Kyungpook National University) ;
  • Jong-Jae Chung (Department of Chemistry, Kyungpook National University) ;
  • Jae-Duck Lee (Department of Chemistry, Dong-A University)
  • 황정의 (경북대학교 자연과학대학 화학과) ;
  • 정종재 (경북대학교 자연과학대학 화학과) ;
  • 이재덕 (동아대학교 자연과학대학 화학과)
  • Published : 1989.04.20
Download PDF
⟨ Previous Next ⟩

Abstract

The heterogeneous rate constants for the electrochemical reduction by $trans-[Co(en)_2X_2](ClO_4)_n$(where X is cyanide, nitrite, ammonia, and isothiocyanate) at mercury and glassy carbon electrode were investigated by cyclic voltammetry, DC polarography, and by using rotating disk electrode. The good linear relationship was obtained between the activation energy of reduction and absorption wave number of complexes on glassy carbon electrode. At mercury electrode, $NO_2^-$ ligated complex showed the large deviation from the linear relationship. The difference in the value of rate constants for $NO_2^-$ ligated complex between mercury and glassy carbon electrode was about three order of magnitude which was much larger than the other complexes. It was suggested that $NO_^-$ ligated complex was reduced by inner-sphere mechanism on mercury electrode from the larger value of activation energy and entropy on mercury than carbon electrode.

$trans-[Co(en)_2X_2](ClO_4)_n$가 Co(II) 상태의 착물로 (X : 시아나이드, 나이트라이트, 암모니아, 그리고 이소티오시아네이트)되는 전극 환원반응 속도상수를 탄소전극에서 순환전압전류법 및 회전원판전극을 이용하여 측정하고 수은전극에서 순환전압전류법 및 펄스폴라로그래피법으로 측정하여 착물의 분광학적 흡수파수와 관계를 조사하였다. 탄소전극에서는 흡수파수가 증가할 때 전극반응의 활성화자유에너지가 증가하며 좋은 직선성을 보이지만 $NO_2^-$가 배위된 착물의 경우에는 수은전극에서 흡수파수와 활성화에너지의 관계가 비선형적이었으며 활성화엔트로피 역시 크게 나타났고 전극반응 전이계수도 크게 얻어졌다. 수은전극에서는$NO_2^-$가 배위된 착물은 다른 착물과 다르게 innersphere 메카니즘으로 환원되며 $NO_2^-$가 수은전극 표면으로 배향되어 전자전이가 일어나는 것으로 제안하였다.

Keywords

References

  1. Kinetic Parameters of Electrode Reactions of Metallic Compounds. R. Tamamushi
  2. J. Electroanal. Chem. v.22 H. Bartelt;S. Landazury
  3. J. Electroanal. Chem. v.23 H. Bartelt;H. Skolandat
  4. Electrochim. Acta. v.16 H. Bartelt
  5. Electrochim. Acta. v.16 H. Bartelt;M. Prugel
  6. J. Electroanal. Chem. v.25 H. Bartelt
  7. J. Electroanal. Chem. v.24 H. Bartelt;H. Skilandat
  8. Electrochim. Acta. v.16 H. Bartelt
  9. Discuss. Farad. Soc. v.26 A. A. Vlcek
  10. Advances in the Chemistry of the Coordination Compounds. A. A. Vlcek;S. Kirshner(ed.)
  11. J. Kor. Chem. Soc. v.33 J. U. Hwang;J. J. Chung;J. D. Lee
  12. Bull. Chem. Soc. Japan. v.41 M. Muto;T. Baba;H. Yoneda
  13. Inorganic Synthesis v.4 H. F. Holtzclaw, Jr.;D. P. Sheetz;B. D. McCarrty
  14. Ann. v.351 A. Werner
  15. Infrared and Raman Spectra of Inorganic and Coordenation Compounds K. Nakamoto
  16. J. A. Chem. Soc. v.72 F. Basolo
  17. Bull. Chem. Soc. Japan. v.29 Y. Shimura;R. Tsuchida
  18. J. Am. Chem. Soc. v.79 I. M. Kolthoff;J. F. Coetzee
  19. Electrochemical Methods A. J. Bard;L. R. Faulkner
  20. Anal. Chem. v.36 R. S. Nicholson;I. Shain
  21. Anal. Chem. v.40 K. B. Oldham;E. P. Parry
  22. J. Am. Chem. Soc. v.102 R. J. Klingler;J. K. Kochi
  23. Electrochemical Methods A. J. Bard;L. R. Faulkner
  24. Progess in Inorganic Chemistry v.5 A. A. Vlcek;F. A. Cotton(Ed.)
  25. Electrochim. Acta. v.23 S. S. Singh;M. S. Verma;H. S. Sharma;H. L. Nigam
  26. The Study of Kinetics and Mechanism of Reactions of Transition Metal Complexes R. G. Wilkins
  27. J. Am. Chem. Soc. v.90 J. L. Sadler;A. J. Bard
  28. J. Phys. Chem. v.67 Z. Glaus;R. N. Adams
  29. Electrochim. Acta. v.28 M. Sharp
  30. Inorg. Chem. v.14 A. M. Bond;R. L. Martin;A. F. Masters