HWAHAK KONGHAK, Vol.40, No.6, 729-734, December, 2002
폴리아닐린의 이차도핑과 전기화학적 특성
The Electrochemical Characteristics and Secondary Doping Effects of Poly[Sodium 4-Styrenesulfonate] Doped Polyaniline
E-mail:
초록
본 연구에서 PSS로 도핑된 EB와 LEB 형태의 폴리아닐린 필름을 ITO전극위에 m-cresol, chloroform 혼합용액을 도포시켜 제조하였다. UV 실험결과로부터 m-cresol에 의한 이차 도핑 효과를 확인 할 수 있었으며, m-cresol의 양이 증가할수록 폴리아닐린 필름의 전도도는 증가하였다. 이차도핑에 의한 전도도 향상은 제조된 폴리아닐린과 m-cresol의 상호작용에 의한 것으로 판단된다. 폴리아닐린의 전기화학적 실험결과 LEB로 제작된 폴리아닐린 전극의 산화ㆍ환원 피크 전류는 EB로 제작된 폴리아닐린 전극보다 더 크고 가역적인 것을 CV를 통해 구할 수 있었다. 또한 전하전달 저항은 m-cresol의 양이 증가할 수록 감소하였으며, LEB/PSS 전극의 전하 전달 저항 값이 EB/PSS 전극보다 작았다. 이것은 CV에서 얻은 경향과 일치하였다. 제조된 폴리아닐린 전극 모두 이중층 용량과 용액저항은 일정하였으며, 용액저항은 주파수에 무관한 인자임을 알 수 있었다. 또한 PSS로 도핑된 폴리아닐린은 가상적인 n형 전도성 고분자의 특성을 나타내었다.
In this study, the polyaniline films of emeraldine base(EB) and lucoemeraldine base(LEB) form chemically doping with poly(sodium-4 styrenesulfonate, PSS) were prepared by casting the mixed solution of chloroform and m-cresol on ITO(indium tin oxide) electrode. By analyzing UV-vis spectra of the mixed solutions, the effects of the secondary doping by m-cresol were obtained. And the conductivity of polyaniline film was increased with increasing m-cresol content. The results suggest that the improvement of conductivity obtained by secondary doping results primarily from interaction of polyaniline and m-cresol. As the results of analyzing cyclic voltammograms, it was known that the redox peak currents of polyaniline electrode prepared from LEB were larger and more reversible than those of polyaniline electrodes prepared from EB. The charge transfer resistances(Rct) of polyaniline electrodes were reduced with increasing m-cresol content, and LEB/PSS electrodes were smaller than EB/PSS electrodes. This result agrees to the analysis of the redox peak current of cyclic voltammograms. The solution resistance and the capacity of electrical double layer almost unchanged in all prepared polyaniline electrodes. It was
confirmed that solution resistance was independent of frequency factor in AC impedance spectra. Also the polyaniline film doping with PSS was revealed pseudo n-type characteristics of conducting polymer.
- MacDiarmid AG, Epstein AJ, Synth. Met., 69, 85 (1995)
- Matveeva ES, Gonzalez-Tejera MJ, J. Electrochem. Soc., 147(3), 1213 (2000)
- Minesaka T, Chem. Soc. Jpn., 1, 1 (1990)
- Kroschwitz JI, "Electrical and Electronic Properties of Polymer," John Wiley & Sons, New York (1988)
- Naoi K, Lien M, Smyrl WH, J. Electrochem. Soc., 138, 440 (1991)
- Morita M, Miyazaki S, Ishikawa M, Matsuda Y, Tajima H, Adachi K, Anan F, J. Electrochem. Soc., 142(1), L3 (1995)
- Okamoto H, Ando Y, Kotaka T, Synth. Met., 96, 7 (1998)
- MacDiarmid AG, Chiang JC, Richter AF, Synth. Met., 18, 285 (1987)
- Wei X, Epstein AJ, Synth. Met., 74, 123 (1995)
- MacDiarid AG, Yang LS, Huang WS, Humphrey BD, Synth. Met., 18, 393 (1987)
- Tsutsumi H, Araki M, Onimura K, Oishi T, Synth. Met., 97, 53 (1998)
- Kim KC, Park JH, Im JH, Han HS, Joe YI, HWAHAK KONGHAK, 36(3), 460 (1998)
- Minesaka T, Denki Kagaku, 58, 369 (1990)
- Ko JM, Chung IJ, Synth. Met., 68, 233 (1995)