• Korean Chemical Engineering Research
• /
• v.52 no.6
• /
• pp.695-700
• /
• 2014

Proton Exchange Membrane Fuel Cells (PEMFC) can generate hydrogen and oxygen from water by electrolysis. But the electrode and polymer electrolyte membrane degrade rapidly during PEM water electrolysis because of high operation voltage over 1.7V. In order to reduce the rate of anode electrode degradation, unsupported $IrO_2$ catalyst was used generally. In this study, Pt/C catalyst for PEMFC was used as a water electrolysis catalyst, and then the degradation of catalyst and membrane were analysed. After water electrolysis reaction in the voltage range from 1.8V to 2.0V, I-V curves, impedance spectra, cyclic voltammograms and linear sweep voltammetry (LSV) were measured at PEMFC operation condition. The degradation rate of electrode and membrane increased as the voltage of water electrolysis increased. The hydrogen yield was 88 % during water electrolysis for 1 min at 2.0V, the performance at 0.6V decreased to 49% due to degradation of membrane and electrode assembly.

• Membrane Journal
• /
• v.27 no.2
• /
• pp.182-188
• /
• 2017

Sulfonated poly(arylene ether sulfone) (SPAES)-3-mercaptopropyl silica gel (3MPTSG) composite membranes with improved oxidative stability were prepared for polymer electrolyte fuel cell application. It has been reported that ether part of main chain of aromatic hydrocarbon based membranes were weak to radical attack to decrease membrane durability. In this study, the hydrophilic inorganic particles were introduced by minimizing a decrease in ion conductivity and increasing an oxidative stability. The composite membranes were investigated in terms of ionic conductivity, ion exchange capacity (IEC), FT-IR, TGA and contact angle, etc. As a result, increasing amount of the 3MPTSG resulted in decrease in proton conductivities and water uptakes at 100% R.H. but enhanced thermal and oxidative stabilities.

• Proceedings of the Membrane Society of Korea Conference
• /
• 2005.05a
• /
• pp.75-78
• /
• 2005

• 한국전기화학회:학술대회논문집
• /
• 2004.10a
• /
• pp.41-41
• /
• 2004

• 한국전기화학회:학술대회논문집
• /
• 2003.07a
• /
• pp.57-61
• /
• 2003

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.65-68
• /
• 2007

전극 막 접합체를 만드는 방법 중 연속식 공정으로서의 데칼법의 장점은 제조공정의 단순화와 두께 균일성 그리고 대량생산 등을 그 예로 들 수 있다. 본 실험에서는 코터를 이용해 전극 막 접합체를 만들기 위해 높은 점도의 촉매 슬러리를 제조하였다. Johnson Mattey 사의 HiSPEC 40 wt% Pt/C 촉매와 Dupont사의 20 wt% Nafion Solution 그리고 물을 이용하여 촉매 슬러리를 제조한 후 코터를 이용하여 데칼법으로 전극 막 접합체를 제조하였다. 완성된 전극 막 접합체의 성능 평가를 실시하였으며 상용화된 전극 막 접합체와 그 특성을 비교 분석을 실시해보았다.

• Membrane Journal
• /
• v.29 no.1
• /
• pp.30-36
• /
• 2019

In this study, we reported a solid-state supercapacitor consisting of titanium nitride (TiN) nanofiber and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT-PSS) conducting polymer electrode and poly(vinyl alcohol) (PVA)-based polymer electrolyte membrane. The TiN nanofiber was selected as electrode materials due to high electron conductivity and 2-dimensional structure which is beneficial for scaffold effect. PEDOT-PSS is suitable for organic/inorganic composites due to good redox reaction with hydrogen ions in electrolyte and good dispersion in solution. By synergetic effect of TiN nanofiber and PEDOT-PSS, the PEDOT-PSS/TiN electrode showed higher surface area than the flat Ti foil substrate. The PVA-based polymer electrolyte membrane could prevent leakage and explosion problem of conventional liquid electrolyte and possess high specific capacitance due to the fast ion diffusion of small $H^+$ ions. The specific capacitance of PEDOT-PSS/TiN supercapacitor reached 75 F/g, which was much higher than that of conventional carbon-based supercapacitors.

• Clean Technology
• /
• v.13 no.2
• /
• pp.99-103
• /
• 2007

Pt/Nafion self-humidifying membranes for Polymer Electrolyte Membrane Fuel Cell (PEMFC) were synthesized via a supercritical-impregnation method. The Nafion 112 membranes were impregnated with Pt(II) acetylacetonate from a supercritical carbon dioxide ($scCO_2$) solution at $80^{\circ}C$ and 19.8 MPa. After the impregnation, the Pt-impregnated Nafion membrane was converted Pt deposited Nafion(Pt/Nafion) membrane by reducing agent, sodium borohydride ($NaBH_4$) under $50^{\circ}C$ and 2 hours. The prepared Pt/Nafion membranes were investigated by SEM, EDS and EPMA. The performance of the Pt/Nafion membranes was examined in PEMFC as a self-humidifying membrane. The cell performance of the Pt/Nafion membrane at $65^{\circ}C$ is better than that of Nafion 112.

• Journal of Hydrogen and New Energy
• /
• v.22 no.5
• /
• pp.579-584
• /
• 2011

Sulfonated poly (ether sulfone)s containing BFBN were prepared from 2,3-bis(4-fluorophenyl)-2-butenedinitrile , 4,4-sulfonyldiphenol and sulfonated 4,4'-difluorodiphenylsulfone sodium salt using potassium carbonate, and followed acidification reaction with 1M $H_2SO_4$. BFBN was prepared from 4-fluorobenzylcyanide, $CCl_4$, NaOH using trimethylbenzylammoniumchloride . Sulfonated poly(ether sulfone)s containing BFBN were studied by FT-IR, $^1H$-NMR spectroscopy, and thermo gravimetric analysis (TGA). The water uptake of synthesized S-PBFBN membranes exhibit 31~62% compared with 28% of Nafion 211. The S-PBFBN membranes exhibit proton conductivities ($80^{\circ}C$, RH 100) of 53.8~117.4 mS/cm compared with 137.4 mS/cm of Nafion 211.

• Applied Chemistry for Engineering
• /
• v.22 no.2
• /
• pp.125-132
• /
• 2011

A unitized regenerative fuel cell (URFC) as a next-generation fuel cell technology was considered in the study. URFC is a mandatory technology for the completion of the hybrid system with the fuel cell and the renewable energy sources, and it can be expected as a new technology for the realization of hydrogen economy society in the $21^{st}$ century. Specifically, the recent research data and results concerning the polymer electrolyte membrane for the URFC technology were summarized in the study. The prime requirements of polymer electrolyte membrane for the URFC applications are high proton conductivity, dimensional stability, mechanical strength, and interfacial stability with the electrode binder. Based on the performance of the polymer electrolyte membrane, the URFC technology combining the systems for the production, storage, utilization of hydrogen can be a new research area in the development of an advanced technology concerning with renewable energy such as fuel cell, solar cell, and wind power.