• 제목/요약/키워드: NiCl₂

검색결과 408건 처리시간 0.03초

Ni/MH 2차 전지용 고용량 Ti계 수소저장합금의 설계에 관한 연구 (A Study on the Alloy Design of High Capacity Ti-Based Metal Hydride for Ni/MH Rechargeable Battery)

  • 이한호;이재영
    • 한국수소및신에너지학회논문집
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    • 제7권1호
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    • pp.19-28
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    • 1996
  • Ti-Mn based hydrogen storage alloy were modified by substituting alloying elements such as Zr, V and Ni in order to design a high capacity MH electrode for Ni/MH rechargeable battery. When V was substituted in Ti-Mn binary system, the crystal structure was maintained as $Cl_4$ Laves phase at a composition of $Ti_{0.2}V_{0.4}Mn_{0.4}$ and $Ti_{0.4}V_{0.2}Mn_{0.4}$ and equilibrium pressure decreased below 1 atm without decreasing hydrogen storage capacity considerably. It was found that Ni should be included in Ti-V-Mn alloy in order to hydrogenate it electrochemically in KOH electrolyte. But substitution of Ni for Mn in Ti-V-Mn system caused the increase of equilibrium pressure above 1atm and decrease of hydrogen storage capacity. Zr was able to increase the reversible hydrogen storage capacity of Ti-V-Mn-Ni alloy without considerable change of hydrogenation properties. The electrochemical discharge capacity of Ti-Zr-V-Mn-Ni system were in the range of 350 - 464mAh/g and among them $Ti_{0.8}Zr_{0.2}V_{0.5}Mn_{0.5}Ni_{1.0}$ alloy had $Cl_4$ Laves single phase and very high electrochemical discharge capacity of 464mAh/g.

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Investigation of Al-Ni Alloys Deposition during Over-discharge Reaction of Na-NiCl2 Battery

  • Kim, Jeongsoo;Jo, Seung Hwan;Park, Dae-In;Bhavaraju, Sai;Kang, Sang Ook
    • 전기화학회지
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    • 제19권3호
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    • pp.57-62
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    • 2016
  • The over-discharging phenomena in sodium-nickel chloride batteries were investigated in relation to decomposition of molten salt electrolyte and consequent metal co-deposition. From XRD analysis, the material deposited on graphite cathode current collector was revealed to be by-product of molten salt electrolyte decomposition. In particular, the result showed that the Ni-Al alloys ($Al_3Ni_2$, $Ni_3Al$ and $Al_3Ni$) were electrochemically deposited on graphite current collectors in line with over-discharging behaviors. It is assumed that the $NiCl_2$ solubility in molten salt electrolytes leads to the co-deposition of Ni-Al alloys by increasing metal deposition potential above 1.6 V (vs. $Na/Na^+$). The cell tests have revealed that the composition of molten salt electrolytes modified by various additives makes a decisive influence on the over-discharging behaviors of the cells. It was revealed that NaOCN addition to molten salt electrolytes was advantageous to suppress over-discharge reactions by modifying the characteristics of molten salt electrolytes. NaOCN addition into molten salt electrolytes seems to suppress Ni solubility by maintaining basic melts. The cell using modified molten salt electrolyte with NaOCN (Cell D) showed relatively less cell degradation compared with other cells for long cycles.

Fe-17%Mn 합금의 진동감쇠능 및 내식성에 미치는 Cr, Ni 첨가의 영향 (Effects of Cr and Ni on Damping Capacity and Corrosion Resistance of Fe-17%Mn Alloy)

  • 김정철;한동운;백진현;김태훈;백승한;이영국
    • 한국주조공학회지
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    • 제25권2호
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    • pp.73-79
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    • 2005
  • Effects of Cr and Ni addition on damping capacity, mechanical property, and corrosion resistance of Fe-17%Mn martensitic alloy have been studied. Martensite start temperature($M_{S}$) of the alloy decreases linearly with increasing Cr and Ni contents up to 15%. The damping capacity decreases gradually from 27 to 22% in specific damping capacity(SDC) with increasing Cr and Ni contents from zero to 10%, and decreases rapidly with further Cr and Ni content in Fe-17%Mn alloy. The tensile strength of the alloy maintains a level of 60 $kgf/mm^{2}$ regardless of Cr content with an elongation of 20 to 25%. But, in case of Fe-17%Mn-x%Ni alloy, the tensile strength decreased rapidly with the Ni content of above 10% because of austenite morphology. Immersion test in 5% NaCl solution leads to the result that the corrosion resistance of the alloy becomes excellent above 10% Cr. From the above results, it is concluded that the optimum Cr content to improve the mechanical property and corrosion resistance of the alloy in 5%NaCl solution with a lesser decrease in damping capacity is about 10%. In the case of 5% $H_{2}SO_{4}$ condition, the Fe-17%Mn-10%Ni is an optimum alloy.

P-Type Doping of Graphene Films by Hybridization with Nickel Nanoparticles

  • Lee, Su Il;Song, Wooseok;Kim, Yooseok;song, Inkyung;Park, Sangeun;Cha, Myung-Jun;Jung, Dae Sung;Jung, Min Wook;An, Ki-Seok;Park, Chong-Yun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.208-208
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    • 2013
  • Graphene has emerged as a fascinating material for next-generation nanoelectronics due to its outstanding electronic properties. In particular, graphene-based field effect transistors (GFETs) have been a promising research subject due to their superior response times, which are due to extremely high electron mobility at room temperature. The biggest challenges in GFET applications are control of carrier concentration and opening the bandgap of graphene. To overcome these problems, three approaches to doping graphene have been developed. Here we demonstrate the decoration of Ni nanoparticles (NPs) on graphene films by simple annealing for p-type doping of graphene. Ni NPs/graphene films were fabricated by coating a $NiCl2{\cdot}6H2O$ solution onto graphene followedby annealing. Scanning electron microscopy and atomic force microscopy revealed that high-density, uniformly sized Ni NPs were formed on the graphene films and the density of the Ni NPs increased gradually with increasing $NiCl2{\cdot}6H2O$ concentration. The formation of Ni NPs on graphene films was explained by heat-driven dechlorination and subsequent particlization, as investigated by X-ray photoelectron spectroscopy. The doping effect of Ni NPs onto graphene films was verified by Raman spectroscopy and electrical transport measurements.

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LiCl-Li2O 용융염에서 Inconel 합금 및 Incoloy 800H의 고온 부식거동 (Hot Corrosion Behavior of Inconel Alloys and Incoloy 800H in Molten LiCl-Li2O Salt)

  • 임종호;최정묵
    • 한국재료학회지
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    • 제23권2호
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    • pp.128-134
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    • 2013
  • A study on the corrosion behavior of Inconel alloys and Incoloy 800H in molten salt of LiCl-$Li_2O$ was investigated at $650^{\circ}C$ for 24-312 hours in an oxidation atmosphere. The order of the corrosion rate was Inconel 600 < Inconel 601 < Incoloy 800H < Inconel 690. Inconel 600 showed the best performance suggesting that the content of Fe, Cr and Ni are the important factor for corrosion resistance in hot molten salt oxidation conditions. The corrosion products of Inconel 600 and Inconel 601 were $Cr_2O_3$ and $NiFe_2O_4$, In case of Inconel 690, a single layer of $Cr_2O_3$ was formed in the early stage of corrosion and an outer layer of $NiFe_2O_4$ and inner layer of $Cr_2O_3$ were formed with an increase of corrosion time. In the case of Incoloy 800H, $Cr_2O_3$ and $FeCr_2O_4$ were observed. Most of the outer scale of the alloys was observed to be spalled from the results of the SEM analysis and the unspalled scale which adhered to the substrate was composed of three layers. The outer layer, the middle one, and the inner one were Fe, Cr, and Ni-rich, respectively. Inconel 600 showed localized corrosion behavior and Inconel 601, 690 and Incoloy 800H showed uniform corrosion behavior. Ni improves the corrosion resistance and too much Cr and/or Fe content deteriorates the corrosion resistance.

Synthesis and Characterization of the Layered Type $(C_nH_{2n+1}NH_3)_2PbCl_4$ System

  • 이수종;김계야;오은주;김규홍;여철현
    • Bulletin of the Korean Chemical Society
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    • 제21권3호
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    • pp.317-320
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    • 2000
  • Layered $K_2NiF_4$type ($C_nH_{2n+1}NH_3)_2PbCl_4$(n=6, 8 and 10) system, or alkylammonium tetrachloroplumbate compound, has been synthesized from $PbCl_2$ and $C_nH_{2n+1}NH_3Cl$ solutions under argon ambient pressure for 12hrs at $90^{\circ}C$. The crystal structure of the compound has been analyzed using X-ray powder diffaction in the range of $5^{\circ}{\leq}2{\theta}{\leq}55^{\circ}$, and all samples assigned to an orthorhombic system. Local distances of the Pb-Cl bond have been determined by Pb $L_{III}$-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. The vibration modes of alkylammonium chains and the absorpton peaks of an excition have been examined by FT-IR and UV-Vis. reflectance spectra, respectively. The phase transition temperatures of the compounds have been studied by using DSC. According to the thermal analysis, two phase transition temperatures have been observed in the compositons of n=8 and 10.

$[Ni(L)](ClO_4)_2$(L: 2,13-bis(2-pyridylmethyl)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,$0^{1.18},0^{7.12}$docosane) 착물의 결정구조 (Crystal Structure of $[Ni(L)](ClO_4)_2$ (L: 2,13-bis(2-pyridylmethyl)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,$0^{1.18},0^{7.12}$]docosane))

  • Park, Ki-Young;Suh, Il-Hwan;Kim, Jing-Gyu;Park, Young-Soo
    • 한국결정학회지
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    • 제10권1호
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    • pp.88-93
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    • 1999
  • The complex [Ni(L)](ClO4)2 (1) (L=2,13-bis(2-pyridylmethyl)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.1807.12]docosane) has been synthesized and characterized by X-ray crystallography. (1) crystallizes in the triclinic, space group P, with a=10.948(2), b=10.948(2), c=14.911(4) , α=93.73(2), β=93.77(2), γ=99.29(2)o, V=1754.8(7) 3, Z=2, R1(wR2) for 5217 observed reflections of [I>2σ(I)] was 0.048(0.099). The coordination environment around nickel(II) ion shows a distorted octahedron with four secondary and tertially amines of the macrocycle and two nitrogen atoms of pyridylmethyl groups.

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Microstructural improvement in polycrystalline Si films by crystallizing with vapor transport of Al/Ni chlorides

  • Eom, Ji-Hye;Lee, Kye-Ung;Jun, Young-Kwon;Ahn, Byung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.315-318
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    • 2004
  • We developed a vapor induced crystallization (VIC) process for the first time to obtain high quality polycrystalline Si films by sublimating the mixture of $AlCl_3$ and $NiCl_2$. The VIC process enhanced the crystallization of amorphous silicon thin films. The LPCVD amorphous silicon thin films were completely crystallized after 5 hours at 480 $^{\circ}C$. It is known that needle-like grains with very small width grow in the Ni-metal induced lateral crystallization. In our new method, the width of grains is larger because the grain can also grow perpendicular to the needle growth direction. Also the interface between the merging grain boundaries was coherent. As the results, a polycrystalline film with superior microstructure has been obtained.

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Ni-W 합금도금용 불용성 양극의 제조 및 특성 연구 (Preparation and Characterization of Insoluble Anodes for Electrodeposition of Ni-W Alloys in Ammoniacal Citrate Bath)

  • 장도연;강성군
    • 한국표면공학회지
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    • 제32권6호
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    • pp.686-694
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    • 1999
  • Insoluble anodes of the Ta/Ir mixed metal oxide for electrodeposition of Ni-W alloy in ammoniacal citrate bath were prepared by thermal decomposition method. Ti plate was etched in boiling oxalic acid solution and coated with ethanol solution of $TaCl_{5}$ and $IrCl_4$ mixed in a fixed ratio, followed by drying and treating at various temperatures. The coating layer of these insoluble anode was characterized by SEM, EDX, XRD and DSC. The decomposition rate of citric acid in plating bath was determined by measuring the $CO_2$ gas evolved at the anodes with Gas Chromatography. Evolution of $CO_2$ gas from Ta/Ir oxide anodes decreased about 5% compared with that of Pt. The $CO_2$ gas evolution was increased with the amount of Ir-oxide in the coatings. The coatings which have more than 40% ratio of Ta content and heat-treated at the temperature higher than $400^{\circ}C$ showed better efficiency

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Evaluation of Iron Nickel Oxide Nanopowder as Corrosion Inhibitor: Effect of Metallic Cations on Carbon Steel in Aqueous NaCl

  • Chaudhry, A.U.;Mittal, Vikas;Mishra, Brajendra
    • Corrosion Science and Technology
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    • 제15권1호
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    • pp.13-17
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    • 2016
  • The aim of this study was to evaluate the use of iron-nickel oxide ($Fe_2O_3$.NiO) nanopowder (FeNi) as an anti-corrosion pigment for a different application. The corrosion protection ability and the mechanism involved was determined using aqueous solution of FeNi prepared in a corrosive solution containing 3.5 wt.% NaCl. Anti-corrosion abilities of aqueous solution were determined using electrochemical impedance spectroscopy (EIS) on line pipe steel (API 5L X-80). The protection mechanism involved the adsorption of metallic cations on the steel surface forming a protective film. Analysis of EIS spectra revealed that corrosion inhibition occurred at low concentration, whereas higher concentration of aqueous solution produced induction behavior.