Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Synthesis of Mesoporous Pt-Au Alloy Electrode by Electrodeposition Method for Direct Methanol Fuel Cell

전기화학적 증착법에 의한 직접 메탄올 연료전지(DMFC)용 메조포러스 백금-금 합금전극제조

  • Park, Eun-Kyung (Regional Innovation Center for Environmental Technology of Thermal Plasma (ETTP), Inha University) ;
  • Ahn, Jae-Hoon (Department of Chemistry, BK School of Molecular Science, Pohang University of Science and Technology) ;
  • Kim, Young-Soo (Regional Innovation Center for Environmental Technology of Thermal Plasma (ETTP), Inha University) ;
  • Kim, Kyung-Hwa (Regional Innovation Center for Environmental Technology of Thermal Plasma (ETTP), Inha University) ;
  • Baeck, Sung-Hyeon (Regional Innovation Center for Environmental Technology of Thermal Plasma (ETTP), Inha University)
  • 박은경 (인하대학교 열플라즈마환경기술연구센터) ;
  • 안재훈 (포항공과대학교 화학과, BK21) ;
  • 김영수 (인하대학교 열플라즈마환경기술연구센터) ;
  • 김경화 (인하대학교 열플라즈마환경기술연구센터) ;
  • 백성현 (인하대학교 열플라즈마환경기술연구센터)
  • Received : 2008.04.18
  • Accepted : 2008.05.08
  • Published : 2008.08.31
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Abstract

Mesoporous Pt-Au alloy films were successfully fabricated on ITO-coated glass by electrodeposition method using tri-blockcopolymer (P123) as a templating agent. The electrolyte consisted of 10 mM hydrogen hexachloroplatinate ($H_2PtCl_6$), 10 mM hydrogen tetrachloroaurate ($HAuCl_4$), and proper amount of P123. For comparison, control samples were electrodeposited without $HAuCl_4$ and P123. Film composition was determined by EDS(Energy Dispersive X-ray Spectroscopy), and the mesoporous structure was confirmed by TEM(Transmission Electron Microscopy). SEM(Scanning Electron Microscopy) was utilized to examine surface morphology, and it was observed that the addition of P123 affected the particle growth, resulting in the significant change of surface morphology. Methanol oxidation and CO oxidation were carried out to investigate electrocatalytic activities of synthesized samples. It was observed that the catalytic activity was strongly dependent on the film compositions. Compared with nonporous electrode prepared without P123 templating, mesoporous films prepared with P123 templating showed much higher catalytic activities and stability for both methanol oxidation and CO oxidation. These enhanced electrocatalytic activities were due to the high surface area and facilitated charge transfer of mesoporous films.

계면활성제(P123)를 주형물질로 사용하여 메조포러스 구조의 Pt-Au 합금박막을 전기화학적 증착법에 의해 ITO가 코팅된 유리 위에 합성하였다. 전해질은 각각 10 mM의 $H_2PtCl_6$와 $HAuCl_4$의 혼합용액에 일정량의 계면활성제를 첨가하여 사용하였다. TEM(Transmission Electron Microscopy) 분석을 통하여 기공구조를 확인하였고, SEM(Scanning Electron Microscopy) 분석을 통하여 합성된 박막의 표면입자의 형태를 확인하였다. 합성된 메조포러스 구조의 Pt-Au 합금박막의 입자 함량비는 EDS(Energy Dispersive X-ray Spectroscopy) 분석으로 조사하였다. 메탄올 산화에 대한 전기화학적 촉매활성과 박막의 안정성을 평가한 결과 메조포러스 구조일 때, 넓은 표면적으로 인해 산화전류밀도가 월등히 증가함을 알 수 있었으며, 순수한 Pt박막과 비교하였을 때 소량의 Au입자의 첨가로 촉매적 안정성이 향상됨을 확인하였다.

Keywords

Acknowledgement

Supported by : 한국학술진흥재단

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