Proton Conductivity and Methanol Permeability of Sulfonated Poly(aryl ether sulfone)/Modified Graphene Hybrid Membranes

술폰화 폴리아릴렌에테르술폰/개질된 그라핀 복합막의 이온전도도 및 메탄올 투과도

  • Huh, Hoon (Korea Institute of Industrial Technology (KITECH)) ;
  • Kim, Deuk-Ju (School of Materials Science and Engineering, i-Cube Center, Gyeongsang National University) ;
  • Nam, Sang-Yong (School of Materials Science and Engineering, i-Cube Center, Gyeongsang National University)
  • 허훈 (한국생산기술연구원) ;
  • 김득주 (경상대학교 나노신소재공학과, 아이큐브 사업단) ;
  • 남상용 (경상대학교 나노신소재공학과, 아이큐브 사업단)
  • Received : 2011.08.25
  • Accepted : 2011.09.22
  • Published : 2011.09.30

Abstract

In this study, to obtain good dispersity of graphene which has excellent conductivity and mechanical strength, the graphene was modified by two different methods. Then the SPAES/graphene hybrid membranes were fabricated from different graphene contents. We compared performance of composite membrane with different preparing method of graphene and content of modified graphene. The morphology of the composite membranes has been investigated using SEM. Chemical structure of modified graphene was analyzed using by FT-IR and EDX. The proton conductivity and methanol permeability of the hybrid membranes were studied with changing graphene content from 0.5 to 3.0 wt.%. The SPAES/modified graphene composite membranes showed high proton conductivity (0.21 S/cm) compared with the SPAES membrane (0.09 S/cm) at $80^{\circ}C$ and 100% relative humidity condition. And the methanol permeability was decreased linearly as the content of modified graphene increased from 0 to 1.5 wt%.

본 연구에서는 뛰어난 전도도와 물리적 강도를 가지는 그라핀의 고른 분산성을 얻기 위하여 두 가지 다른 방법으로 그라핀을 개질시켰다. 그리고 SPAES/그라핀 복합막은 각기 다른 함량을 첨가하여 제조되었으며 그라핀의 제조방법과 첨가된 그라핀의 함량에 따른 성능을 비교하였다. 복합막의 모폴로지는 SEM을 이용하여 관찰하였으며 개질된 그라핀의 화학적 구조는 FT-IR과 TGA를 사용하여 분석되었다. 그라핀의 함량변화가 0.5~3.0 wt% 일 때 복합막의 이온전도도와 메탄올 투과도를 측정하였으며 $80^{\circ}C$, 100% 가습상태에서 SPAES/그라핀 복합막의 이온전도도(0.216 S/cm)는 순수한 SPAES 전해질 막보다 높은 이온전도도(0.098 S/cm)를 나타내었으며 그라핀의 함량이 1.5 wt%까지 증가될 때 메탄올 투과도는 감소되었다.

Keywords

References

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