• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.110-110
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• 1999

Polyvinylidenefluoride (PVDF) is most used in piezoelectric polymer industry. Electrode effect on the electrical properties of PVDF has been investigated. al has been used due to fair adhesion for PVDF. Work function of metal plays an important role on the electrical properties of ferroelectrics for top and /or bottom electrode. However, Al has much lower work function than Pt or Au and so leakage current of Al/PVDF/Al may be large. Pt or Au has not been used for electrode of PVDF system due to poor adhesion. PVDF irradiated by Ar+ ion beam with O2 environment takes good adhesion to inert metal. Contact angle of PVDF to triple distilled water was reduced from 75$^{\circ}$ to 31$^{\circ}$ at 1$\times$1015 Ar+/cm2. Working pressure was 2.3$\times$10-4 Torr and base pressure was 5$\times$10-6 Torr. Pt was deposited by ion beam sputtering and thickness of pt film was about 1000$\AA$. in previous study, enhancing adhesion of Pt on PVDF was shown. in this study, effect of electrode on PVDF will be represented.

• 대한화학회지
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• 제33권4호
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• pp.388-398
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• 1989

기체 감응막전극을 이용하여 수용액 중의 아질산이온을 연속${\cdot}$자동화법으로 정량하는 방법을 개발하였다. 이 방법에서 최종검출기로 쓴 이온선택성 전극은 관형 PVC막 pH 전극이었다. 장치계의 최적조건에서 구한 아질산이온 표준시료에 대한 전극의 감응기울기는 63.5mV/decade 이었으며, 직선감응 범위는 $2.5{\times}10^{-4}\; M{\sim}7.5 {\times} $10^{-2}$M 이었고, 검출한계는 $8.0{\times} 10^{-5}$M이었다. 이 방법은 다른 정량법보다 산성기체종의 방해를 적게 받을 뿐만 아니라 정량에 필요한 시간도 훨씬 단축할 수 있었다.

• 한국재료학회지
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• 제29권8호
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• pp.505-510
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• 2019

Zn-ion supercapacitors (ZICs) show high energy densities with long cycling life for use in electronic devices. Porous Zn electrodes as anodes for ZICs are fabricated by chemical etching process using optimized conditions. The structures, morphologies, chemical bonding states, porous structure, and electrochemical behavior are examined. The optimized porous Zn electrode shows a root mean square of roughness of 173 nm and high surface area of $153{\mu}m^2$. As a result, ZIC using the optimized porous Zn electrode presents excellent electrochemical performance with high specific capacitance of $399F\;g^{-1}$ at current density of $0.5A\;g^{-1}$, high-rate performance ($79F\;g^{-1}$ at a current density of $10.0A\;g^{-1}$), and outstanding cycling stability (99 % after 1,500 cycles). The development of energy storage performance using synergistic effects of high roughness and high surface area is due to increased electroactive sites by surface functionalization of Zn electrode. Thus, our strategy will lead to a rational design and contribute to next-generation supercapacitors in the near future.

• 공업화학
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• 제24권3호
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• pp.247-252
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• 2013

반응시간을 변화시키면서 poly(ether ether ketone) (PEEK)을 황산과 반응시켜 술폰화도가 다른 sulfonated PEEK (SPEEK)를 합성하였다. 제조한 SPEEK를 탄소전극 표면에 코팅하여 이온선택성 복합탄소전극(ion-selective composite carbon electrode, ISCCE)을 제조하였다. 임피던스 분석을 통해 제조한 ISCCE의 비정전용량과 전기저항을 측정하였다. 술폰화 반응 시간에 따라 SPEEK의 이온교환용량은 1.60~2.57 meq/g으로 측정되었다. 그러나 이온교환용량이 2.5 meq/g 이상에서는 SPEEK가 일부 물에 용해되어 ISCCE 제조에 부적합하였다. ISCCE에 대한 정전용량을 측정한 결과 코팅된 SPEEK의 이온교환용량이 증가함에 따라 정전용량도 증가하였으며 코팅하지 않은 탄소전극에 비해 최대 20%까지 향상되었다. 또한 코팅층의 전기저항은 SPEEK의 이온교환용량이 증가함에 따라 크게 감소하였다. 따라서 SPEEK가 코팅된 ISCCE를 이용하여 기존 축전식 탈염(capacitive deionization, CDI) 공정의 탈염효율을 크게 향상시킬 수 있을 것으로 기대된다.

• 공업화학
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• 제9권4호
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• pp.574-578
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• 1998

전기화학적 이온교환전극을 양이온 교환수지 Amberlite IRP-64와 결합제로서 Stylen-Buthylene-Rubber (SBR)를 혼합하여 압축성형 방법으로 제작하여, 전극전위와 전해질의 pH에 따른 구리이온의 흡착과 용출특성을 고찰하였다. 흡착공정에서는 -1800 mV에서 최대 흡착속도를 나타내었으며 90분 경과 후,92%의 흡착율을 나타내었다. 용출공정의 경우, 본 실험영역에서는 전위의 증가에 비례하여 용출율은 증가되어 나타났으며, 3600 mV에서 50분 이후 88%의 용출율을 나타내었다. 전기화학적 이온교환 전극 근처의 국부적인 pH 변화는 흡착과 용출공정에 크게 영향을 미치는 것으로 사료되며, 전해질의 pH가 각각 염기성과 산성에서 높은 흡착율과 용출율을 나타내었다.

• 전기학회논문지
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• 제56권10호
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• pp.1791-1795
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• 2007

Small ions generated at conductor corona sources remain in the atmosphere until they recombine with ions of opposite polarity, attach to aerosols, or make contact with an object. Ion current density is major factor to design conductor configuration of DC overhead transmission line. Several techniques have been used to measure the ion current of HVDC overhead transmission line. In this study, the ion current density was measured by a plate electrode made of a metal flat board at DC corona cage. The sensitivity of the plate electrode is $0.156uA/m^2/V$. To obtain an useful database on corona discharge, it is necessary to do corona test on several kinds of conductor bundles. Therefore, a number of experiments were conducted on several kinds of conductor bundles. To reliably analyze ion effects, corona cage test data were obtained over a long period of time under various weather conditions and expressed as a statistical distribution. Ion current density distribution in foul weather shows a significant increase in levels over the corresponding fair weather. Based on this results, we evaluated the environmental characteristic caused by ion flow of three candidated conductor bundles.

• 대한화학회지
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• 제36권5호
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• pp.638-643
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• 1992

황화이온검출기로서 2가지 형태의 연속 flow-through 전극계의 분석적 감응성질을 조사하고, 최적조건에서 그들의 감응특성을 직접 비교하였다. 두 검출계에 있어서 측정한 봉우리전위를 황화이온농도의 대수값과 관련지웠으며, 적어도 시간당 20개의 시료를 정량할 수 있었다. pH전극법에서는 투석기를 지나 흘러가는 recipient stream의 pH를 측정하였다. 장치는 연속흐름형의 기체투석기가 관형 polymer 막전극과 연결되도록 설계되어 있다. 이 방법의 최적실험조건은 recipient $5.0 {\times} 10^{-5} M NaOH ＋ 5.0 {\times} 10^{-3} M$ NaCl과 diluent 0.10M $H_2SO_4$이며, recipient stream, diluent stream 및 시료의 유속은 모두 1.0ml/min이다. 황화이온 전극법에서는 시판하는 황화이온선택성 전극을 flow-through cell 속의 황화이온을 검출하는 데에 썼다. 이 방법의 최적실험조건인 황화이온 산화방지 완충제(1.0M NaOH 용액에 3.5g 아스코르브산과 7.6g $Na_2EDTA$를 용해)와 시료의 유속은 각각 1.4 ml/min와 1.0 ml/min이다.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1593-1596
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• 2006

The polymeric membrane electrodes based on N,N'-bis-pyridin-2-ylmethylene-naphthalene-1,8-diamine as an ion carrier were prepared and tested for the copper-ion selective electrode. The membrane has a linear dynamic range between $10^{-6}$ and $10^{-2}$ M with a Nernstian slope of 29.6 mV per decade, and its detection limit was $10^{-5.62}$M. The potentiometric response is independent of the pH range of 3-5. The proposed electrode showed good selectivity and response for $Cu^{2+}$ over a wide variety of other metal ions in pH 4.0 buffer solutions.

• Journal of Electrochemical Science and Technology
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• 제3권4호
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• pp.165-171
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• 2012

An experimental study of mass transfer to an amalgamated copper rotating disc electrode has been employed to determine an empirical correlation for the mass transfer rate in laminar flow. The study was performed in a three-electrodes configuration using 0.1 M boric acid and 0.1M potassium chloride as supporting electrolyte with Zn (II) concentration in the range (25-100 mg $dm^{-3}$). Polarization curves at different zinc ion concentration are reported. Hydrogen and oxygen reduction has also been considered.The diffusion coefficients and mass transfer coefficient were obtained using limiting diffusion current technique based on zinc ion reduction. A least squares analysis indicates that the laminar flow results for 13067 < Re > 57552 and 550 < Sc > 1390 can be correlated by the following equation with correlation coefficient (CR) equal to 0.98: $sh=0.61Re^{0.5}Sc^{1/3}$.

• 설비공학논문집
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• 제16권4호
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• pp.318-323
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• 2004

When a strong electric field is applied between a sharply curved electrode and a blunt surface, the corona may result in a gas movement in the electrode gap which is directed toward the blunt surface. That is called the corona wind. It enhances heat and mass transfer between the surface and the surrounding gas. Moreover such enhancement causes no noise or vibration, which can be applied in complex, isolated geometries, and allows simple control of surface temperatures. This paper examines the relationship between the corona wind and the relative humidity. The facility consists of high voltage power supply thin tungsten wire, plate electrode, multimeter, microammeter and flow meter. Gas velocity is a linear function of voltage, relative humidity and is proportional to the square root of the current. The maximum velocities for the positive and negative corona discharge are 1.9 m/s (2.74 CMM/m), 1.5 m/s(2.15 CMM/m), respectively.