• 멤브레인
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• 제15권2호
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• pp.141-146
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• 2005

본 연구에서는 흑연, 열경화성 수지, 그리고 카본 블랙을 사용하여 조성과 제조 조건을 달리하여서 탄소 복합체를 제조하였다. 제조된 탄소 복합체의 고분자 전해질 연료전지용 bipolar plate로의 응용 가능성을 살펴보기 위하여 연속 흐름 기체 투과 장치를 사용하여서 산소의 투과도를 측정하였다 실험 결과 카본 블랙의 양이 증가할수록 산소 투과도가 증가하였으며, 탄소 복합체의 성형 시간이 증가할수록 투과도가 감소하였다 반면에 성형 압력은 산소 투과도에 큰 영향을 미치지 않음을 알 수 있었다.

• The Korean Journal of Ceramics
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• 제5권4호
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• pp.353-356
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• 1999

Highly proten-conductive elastic composites have been successfully prepared from $H_3PO_4$-doped silica gel and styrene-ethylene-butylene-styrene block elastic copolymer. In addition solid state electric double-layer capacitors have been fabricated using the composite as an electrolyte and activated carbon powders(ACP) hybridized with the composite as a polrizable electrode. The cyclic voltammogram of the electric double-layer capacitor fabricated demonstrated that electric charge was stored in the elecric double-layer at the interface between the polarizable electrode and the electrolyte. The value of capacitance of the capacitor was 10 F/(gram of total ACP), which was comparable to that of the capacitors using conventional liquid electrolytes.

• 전기화학회지
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• 제10권3호
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• pp.169-174
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• 2007

화학적 중합방법을 이용하여 HWNT/DAAQ를 합성하여 전기화학적 캐패시터용 전극 소재로서 전기화학적 특성을 연구하였다. XRD pattern 결과에서 MWNT/DAAQ의 표면에 DAAQ가 oligomer 상태로 존재하는 것을 확인 하였으며, SEM image를 통해 표면을 관찰하였고, TCA를 통해 열적안정성을 확인하였다. 활성탄과 MWNT/DAAQ에 기초한 전극의 용량은 1M의 $H_2SO_4$ 전해질 상에서 97F/g의 비방전용량을 확인되었으며, 또한 HWNT/DAAQ 복합 전극은 우수한 전기화학적 거동을 보이는 것을 관찰하였다.

• Rapid Communication in Photoscience
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• 제2권3호
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• pp.82-84
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• 2013

We fabricated dye-sensitized solar cells (DSSCs) with $TiO_2$ nanowire (NW)/nanoparticle (NP) composite and solidified nanogel as the photoelectrode and electrolyte, respectively. $TiO_2$ NWs were generated via pore-infiltration of titanium (IV) isopropoxide (TTIP) into a track-etched polycarbonate membrane with a pore diameter of 100 nm, followed by calcination at $500^{\circ}C$. Energy conversion efficiency of $TiO_2$ NW/NP-based DSSCs was always higher than that of NP-based cells. We attributed this to improved light scattering and electron transport by $TiO_2$ NWs, as verified by intensity modulation photocurrent spectroscopy (IMPS) and intensity modulation photovoltage spectroscopy (IMVS) analyses. Quasi-solid-state DSSCs with NW/NP composites exhibited 5.0% efficiency at 100 $mW/cm^2$, which was much greater than that of NP-based cells (3.2%).

• 한국세라믹학회지
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• 제42권12호
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• pp.793-799
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• 2005

A composite cathode of LSCF$(La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_3)\;and\;GDC\; (Gd_2O_3-doped\;CeO_2:Ce_{0.9}Gd_{0.1}O_{1.95_})$ was characterized in terms of an electrode response, using a point contact in an Yttria-Stabilized Zirconia (YSZ) electrolyte incorporated into AC two-point impedance spectroscopy. The point-contacted configuration amplifies the responses occurring near the YSZ/cathode interface through the aligned point contact on the planar LSCF/GDC electrode. The point contact interface increases the bulk resistance allowing the estimation of the point contact geometry and resolving the electrode-related responses. The resultant impedance spectra are analyzed through an equivalent circuit model constructed by resistors and constant phase elements. The bulk responses can be resolved from the electrode-related portions in terms of spreading resistance. The electrode-related polarizations are measured in terms of temperature and oxygen partial pressure. The modified impedance spectroscopy is discussed in terms of methodology and analytical aspects, toward resolving the electrode-polarization issues in solid oxide fuel cells.

• 한국재료학회지
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• 제32권10호
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• pp.429-434
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• 2022

There is ongoing research to develop lithium ion batteries as sustainable energy sources. Because of safety problems, solid state batteries, where electrolytes are replaced with solids, are attracting attention. Sulfide electrolytes, with a high ion conductivity of 10^-3 S/cm or more, have the highest potential performance, but the price of the main materials is high. This study investigated lithium hydride materials, which offer economic advantages and low density. To analyze the change in ion conductivity in polymer electrolyte composites, PVDF, a representative polymer substance was used at a certain mass ratio. XRD, SEM, and BET were performed for metallurgical analyses of the materials, and ion conductivity was calculated through the EIS method. In addition, thermal conductivity was measured to analyze thermal stability, which is a major parameter of lithium ion batteries. As a result, the ion conductivity of LiH was found to be 10^-6 S/cm, and the ion conductivity further decreased as the PVDF ratio increased when the composite was formed.

• 멤브레인
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• 제18권2호
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• pp.116-123
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• 2008

폴리스티렌-블록-폴리히드록에틸 메타크릴레이트(PS-b-PHEMA), 술포석시닉산(SA), 인텅스텐산(PWA)으로 구성된 수소 이온 전도성 나노복합 고분자 전해질막을 제조하였다. 폴리히드록에틸 메타크릴레이트(PHEMA) 블록의 히드록실그룹(-OH)와 술포석시닉산(SA)의 -COOH 그룹과의 에스테르 반응에 의하여 전해질막을 가교시켰다. 폴리헤테로산(PWA)을 도입했을 때, $SO_3^-$ 그룹의 신축 밴드가 $1187cm^{-1}$에서 $1158cm^{-1}$로 낮아졌으며, 이는 PWA 입자가 전해질막의 술폰산 그룹과 상호작용함을 나타낸다. PWA 함량이 30wt%가 되었을 때, 상온 전도도는 0.045에서 0.062S/cm로 증가되었으며, 이는 PWA 입자의 고유 전도도 특성과 전해질막의 술폰산기의 산도가 증가했기 때문이다. 또한 30wt%를 함유한 복합 전해질막은 $100^{\circ}C$에서는 최대 0.126 S/cm의 수소 이온 전도도를 나타내었다 PWA가 첨가됨에 따라 복합 전해질막의 열적특성 또한 증가하였다.

• Korean Chemical Engineering Research
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• 제57권3호
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• pp.413-419
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• 2019

최근 화석연료기반에서 친환경 수소 기반의 청정에너지원으로 전환되는 세계적 흐름에 따라, 수소연료전지의 고성능 저가격 핵심 소재 기술 개발에 많은 관심이 이루어지고 있다. 그 가운데 연료전지의 전해질로 사용되는 강화복합막의 기술 도입은 과불소계 술폰산 이오노머(Perfluorosulfonic acid, PFSA) 양의 감소 및 막 두께 감소를 통한 가격 저감 및 셀 저항 감소, 치수 안정성 개선 그리고 계면 안정성에 대한 확보가 가능하여 최종적으로 연료전지 성능 향상과 가격절감이 동시에 가능하다. 본 연구에서는 연료전지용 불소계 전해질 강화복합막 코팅 공정에서 이오노머 분산용매에 따라 막 형성 및 물성 변화와 연료전지 성능에 미치는 영향에 대해 연구하였다.

• 한국수소및신에너지학회논문집
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• 제28권1호
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• pp.17-23
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• 2017

Polyether ether ketone (PEEK) composite including tungstophosphoric acid(TPA) membranes have been intensively investigated for polymer electrolyte membrane water electrolysis (PEMWE) and thus covalently linked sulfonated polyether ether ketone (CL-SPEEK) with captured TPA composite membranes were prepared and characterized. Sulfonated polyether ether ketone (SPEEK) was prepared in sulfonation of PEEK and was cross-linked with 1,4 diiodobutane. The carbonyl group of SPEEK was reduced with $NaBH_4$ and 3-isocyanatepropyltriethoxysilane (ICPTES) was added. The TPA captured composite was prepared in reaction of TPA with 3-mercaptopropyltrime thoxysilane (MPTMS). The polymer composite membranes showed better thermostability and electrochemical properties than SPEEK. The membranes were prepared by sol-gel casting method. The polymer composite membrane featured 0.1285 S/cm of proton conductivity at $80^{\circ}C$ and outstanding durability.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2969-2973
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• 2014

A new process to fabricate a composite LSCF-Ag cathode material for SOFCs by electron beam (e-beam) irradiation process has been suggested for operation under intermediate temperature range of $600-700^{\circ}C$. A composite LSCF-Ag cathode with uniformly coated Ag nanoparticles on the surface of the LSCF material was prepared by a facile e-beam irradiation method at room temperature. The morphology of the composite LSCF-Ag material was analyzed using a TEM, FE-SEM, and EDS. The prepared composite LSCF-Ag material can play a significant role in increasing the electro-catalytic activities and reducing the operating temperature of SOFCs. The performance of a tubular single cell prepared using the composite LSCF-Ag cathode, YSZ electrolyte and a Ni/YSZ anode was evaluated at reduced operating temperature of $600-700^{\circ}C$. The micro-structure and chemical composition of the single cell were investigated using a FE-SEM and EDS.