• Title/Summary/Keyword: Anode

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Electoless Ni Plating on Alumina Powder to Application of MCFC Anode Material (MCFC anode 대체 전극 개발을 위한 분말 알루미나 상의 무전해 Ni 도금 연구)

  • Kim, Ki-Hyun;Cho, Kye-Hyun
    • Journal of the Korean institute of surface engineering
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    • v.40 no.3
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    • pp.131-137
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    • 2007
  • The typical MCFC (molten carbonate fuel cell) anode is made of Ni-10%Cr alloy. The work of this paper is focused concerning long life of anode because Ni-10% Cr anode is suffering from sintering and creep behavior during cell operation. Therefore, Ni-coated Alumina powder($20{\mu}m$) was developed by electroless nickel plating. Optimum condition of electroless nickel coation on $20{\mu}m$ alumina is as follows: pH 11.7, temperature $65{\sim}80^{\circ}C$, powder amount $100cm^2/l$. The deposition rate for Ni-electroless plating was as a function of temperature and activation energy was evaluated by Arrhenius Equation thereby activation energy calculated slope of experimental data as 117.6 kJ/mol, frequency factor(A) was $6.28{\times}10^{18}hr^{-1}$, respectively.

A shorted anode p-i-n double injection seitchning device (양극이 단락된 p-i-n 이중주입 스위칭 소자)

  • 민남기;이성재;박하영
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.7
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    • pp.69-76
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    • 1995
  • A new device structure has been developed for p-i-n switches. In this structure, the phosphorus-diffused n$^{+}$ layter adjacent to the boron-doped anode is used to short the p$^{+}$ anode-channel(i-region). This change in the anode electrode structure results in a significant improvement in the threshold voltage-to-holding voltage($V_{Th}/V_{h}$) ratio, which is due to the suppression of the hold injection from the anode by the n$^{+}$ layer. The shorted anode p-i-n devices of a 100 .mu.m channel length show an extremely high threshold voltage in the 250~300 V range and a low holding voltage in the 5~9 V range. These features of the device are expected to acdelerate their practical application to power switching circuits.

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A Study on the Sacrificial Anode for Imparting High Capabilities to Cathodic Protection (전기방식시 적용되는 희생양극의 성능개발에 대한 연구)

  • 김성종
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.1
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    • pp.37-42
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    • 1998
  • Al alloy anode is mostly used for protecting marine structures such as pier steel piles and ship's body. Recently it has been reported that the life of Al alloy anode has been shortened significantly than the original design life. It is suggested that the suspected reasons for this problem mentioned above seems to be the improper protection design of alloy of anode on sea water regardless of environmental facotrs such as flow rate, temperature, contamination degree etc. However there is few paper about to the sea water contamination degree affecting to the life of Al alloy anode. In this study, the property of Al alloy anode was investigated as a parameter of sea water contamination degree such as variation of pH 2, 4, 6, 8, 10 and each sea port's contaminated waters.

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Fuel-Flexible Anode Architecture for Solid Oxide Fuel Cells

  • Hwan Kim;Sunghyun Uhm
    • Applied Chemistry for Engineering
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    • v.34 no.3
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    • pp.226-240
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    • 2023
  • This paper provides an overview of the trends and future directions in the development of anode materials for solid oxide fuel cells (SOFCs) using hydrocarbons as fuel, with the aim of enabling a decentralized energy supply. Hydrocarbons (such as natural gas and biogas) offer promising alternatives to traditional energy sources, as their use in SOFCs can help meet the growing demands for energy. We cover several types of materials, including perovskite structures, high-entropy alloys, proton-conducting ceramic materials, anode on-cell catalyst reforming layers, and anode functional layers. In addition, we review the performance and long-term stability of cells based on these anode materials and assess their potential for commercial manufacturing processes. Finally, we present a model for enhancing the applicability of fuel cell-based power generation systems to assist in the realization of the H2 economy as the best practice for enabling distributed energy. Overall, this study highlights the potential of SOFCs to make significant progress toward a sustainable and efficient energy future.

Mechanism for Ni/YSZ Nano-composite Anode from Spherical Core-shell Formation

  • An, Yong-Tae;Choe, Byeong-Hyeon;Ji, Mi-Jeong;Gu, Ja-Bin;Hwang, Hae-Jin
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.10a
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    • pp.31.2-31.2
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    • 2011
  • We studied a method of manufacturing an anode to restrict contraction in reducing NiO/YSZ by uniformly mixing. In order to mix Ni and YSZ, a sub-micron Ni core surface was coated at high-speed by a mixture of nano-sized YSZ and a spherical core-shell was subsequently formed. The micron-sized core-shell anode powder was then heat treated at $400{\sim}1,450^{\circ}C$ in an air atmosphere and Ni was extruded and synthesized in nano-size. Subsequently, when the nano-sized mixture of the anode was heat treated and maintained at a temperature of $1,450^{\circ}C$, the anode was manufactured, where Ni and YSZ were uniformly distributed with the nano-structure. According to the nano-sized anode powder synthesis process, Ni particles were oxidized at $400{\sim}500^{\circ}C$ and became spherical by surface tension. In the case of the spherical core Ni powder, the heat treatment temperature rose to $1,250^{\circ}C$ and then a gap between the internal and external pressures occurred due to thermal and tensile stresses. A crack subsequently appeared on the surface, and the heat treatment temperature was increased continuously to increase the pressure gap and then the core Ni extruded as a nano-sized powder, Ni and YSZ uniformly distributed. It was found that the anode of 50~200 nm with a consistent structure obtained in this study has electric conductivity that is approximately 3 times larger than that of a commercial anode.

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Crystallographic Effects of Anode on the Mechanical Properties of Electrochemically Deposited Copper Films (아노드의 결정성에 따른 전기도금 구리박막의 기계적 특성 연구)

  • Kang, Byung-Hak;Park, Jieun;Park, Kangju;Yoo, Dayoung;Lee, Dajeong;Lee, Dongyun
    • Korean Journal of Materials Research
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    • v.26 no.12
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    • pp.714-720
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    • 2016
  • We performed this study to understand the effect of a single-crystalline anode on the mechanical properties of as-deposited films during electrochemical deposition. We used a (111) single- crystalline Cu plate as an anode, and Si substrates with Cr/Au conductive seed layers were prepared for the cathode. Electrodeposition was performed with a standard 3-electrode system in copper sulfate electrolyte. Interestingly, the grain boundaries of the as-deposited Cu thin films using single-crystalline Cu anode were not distinct; this is in contrast to the easily recognizable grain boundaries of the Cu thin films that were formed using a poly-crystalline Cu anode. Tensile testing was performed to obtain the mechanical properties of the Cu thin films. Ultimate tensile strength and elongation to failure of the Cu thin films fabricated using the (111) single-crystalline Cu anode were found to have increased by approximately 52 % and 37 %, respectively, compared with those values of the Cu thin films fabricated using apoly-crystalline Cu anode. We applied ultrasonic irradiation during electrodeposition to disturb the uniform stream; we then observed no single-crystalline anode effect. Consequently, it is presumed that the single-crystalline Cu anode can induce a directional/uniform stream of ions in the electrolyte that can create films with smeared grain boundaries, which boundaries strongly affect the mechanical properties of the electrodeposited Cu films.

Electrochemical Behavior of Si/Cu/Graphite Composite Anode for Lithium Secondary Battery (리튬이차전지용 Si/Cu/Graphite 복합체 음극의 전기화학적 거동)

  • Kim, Hyung-Sun;Chung, Kyung-Yoon;Cho, Won-Il;Cho, Byung-Won
    • Journal of the Korean Electrochemical Society
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    • v.12 no.2
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    • pp.162-166
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    • 2009
  • The carbon-coated Si/Cu powders were synthesized by mechanical ball-milling and hydrocarbon gas decomposition methods at high temperature. The carbon-coated Si/Cu powder was used as anode for lithium secondary battery and its electrochemical behavior was investigated. In addition, the carbon-coated Si/Cu/graphite composite anode material was prepared using natural graphite powder and their electrochemical characteristics were compared with natural graphite anode. The specific capacity of carbon-coated Si/Cu anode increased to the initial 10 cycles. The carbon-coated Si/Cu/graphite composite anode exhibited the reversible specific capacity of 450mAh/g and the first cycle efficiency of 81.3% at $0.25mA/cm^2$. The cycling performance of the composite anode was similar to that of pure graphite anode except the reversible specific capacity value.

Influence of the Thin Anode Geometry on the Performance of Molten Carbonate Fuel Cells (얇은 연료극 구조가 용융탄산염 연료전지 성능에 미치는 영향)

  • Seo, Dong-Ho;Park, Dong-Nyeok;Yoon, Sung-Pil;Han, Jong-Hee;Oh, In-Hwan
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.5
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    • pp.599-608
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    • 2011
  • The Ni-Al anodes of the molten carbonate fuel cell (MCFC) with three different structures were successfully fabricated in order to reduce the thickness of the anode down to 0.3 mm; one was the non-supported anode made by a conventional tape casting method, and others were the supported anodes made by lamination or direct casting on the nickel screen. It was seen from the physical analyses and cell operation that the supported thin anodes made by direct casting showed good mechanical strength and cell performance because of a good contact between the anode materials and the support. The single cell using the above anode showed the cell voltage of 0.858 V at the current density of 150$mA/cm^2$ with the nitrogen cross-over of only 0.6% at the operation time of 1,000 h, which was similar to the performance of the conventional thick (0.7 mm) anode. The ability to utilize a thin configuration of anode should cut down the amount of nickel alloy and consequently reduce its manufacturing cost.

A new cleaning concept for display process with electrolyzed anode water (전해 양극수를 이용한 디스플레이 신 세정 공정)

  • Choi Minki;Cha Jiyung;Kim Younggeun;Ryoo Kunkul
    • Proceedings of the KAIS Fall Conference
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    • 2004.11a
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    • pp.99-102
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    • 2004
  • Display process has adopted RCA clean, being applied to large area and coped with environmental issue for last ten years. However, the approaching concept of ozonized, hydrogenised, or electrolyzed water cleaning technologies is within RCA clean paradigm. In this work, only electrolyzed anode water was applied to clean particles and organics as well as metals based on Pourbaix concept, and as a test vehicle, MgO particles were introduced to prove the new concept. The electrolyzed anode water is very oxidative with high oxidation reduction potential(ORP) and low in pH of more than 900mV and 3.1, respectively. MgO particles were immerged in the anode water and its weight losses due to dissolution were measured with time. Weight losses were in the ranges of 100 to 500 micrograms in 250m1 anode waters depending on their ORP and pH. Therefore it was concluded that the cleaning radicals in the anode water was at least in the range of 1 to 5E20 ea per 250 ml anode water equivalent to IE18 ea/cm3. Hence it can be assumed that the anode water be applied to display cleaning since 1E10 to IE15 ea/cm3 ranges of contaminants are being treated. In addition, it was observed that anode water does not develop micro-roughness on hydrophobic surface while it does on the native silicon oxide.

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