• Title/Summary/Keyword: $Ni_2O_3$

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Synthesis and Conductivity Properties of $LaNiO_3$ Ceramic Conductors ($LaNiO_3$전도성 세라믹의 합성과 도전특성)

  • Cho, Jung-Ho;Cho, Joo-Hun;Kim, Kang-Eun;Chung, Su-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.406-409
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    • 2001
  • The conductivity properties and synthesis of $LaNiO_{3}$ ceramics from $La_{1+\delta}NiO_{3}(\delta=-0.06,0,0.06)$ were investigated. A single perovskite phase was realized at $800^{\circ}C$. $La_{2}NiO_{4}$ and other unexpected oxide were observed at $1000^{\circ}C$. The Microstructure was showed clearly that it is a low density porous material. $LaNiO_3$ ceramic showed a metallic conductivity. The conductivity of La rich samples had a higher value than the La poor samples.

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Synthesis and Conductivity Properties of LaNiO$_3$ Ceramic Conductors (LaNiO$_3$전도성 세라믹의 합성과 도전특성)

  • 조정호;조주현;김강언;정수태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.406-409
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    • 2001
  • The conductivity properties and synthesis of LaNiO$_3$ ceramics from La$\sub$1+$\delta$/NiO$_3$($\delta$=--0.06, 0, 0.06) were investigated. A single perovskite phase was realized at 800$^{\circ}C$. La$_2$NiO$_4$ and other unexpected oxide were observed at 1000$^{\circ}C$. The Microstructure was showed clearly that it is a low density porous material. LaNiO$_3$ ceramic showed a metallic conductivity. The conductivity of La rich samples had a higher value than the La poor samples.

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The Novel Synthetic Route to Li$Co_{y}Ni_{1-y}O_{2}$ as a Cathode Material in Lithium Secondary Batteries

  • Gang, Seong Gu;Ryu, Gwang Seon;Jang, Sun Ho;Park, Sin Jeong
    • Bulletin of the Korean Chemical Society
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    • v.22 no.12
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    • pp.1328-1332
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    • 2001
  • The structure and electrochemical properties of the LixCoyNi1-yO2 (y=0.1, 0.3, 0.5, 0.7, 1.0) system synthesized by solid state reaction with various starting materials have been investigated to optimize the characteristics and synthetic conditions of the LixCoyNi1-yO2. The first discharge capacities of LixCoyNi1-yO2 are 60 mAh/g-180 mAh/g with synthetic conditions. Among them, the LixNi0.7Co0.3O2, which was prepared with LiOH, NiO, and Co3O4 at $850^{\circ}C$, had the best electrochemical properties. The first discharge capacity of the compound was 180 mAh/g.

Steam methane reforming performance of Ni/Al2O3 composite catalysts prepared via a hydrothermal-infiltration method

  • Sang-Hun Lee;Ki-Tae Lee
    • Journal of Ceramic Processing Research
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    • v.21 no.3
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    • pp.296-301
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    • 2020
  • Ni as a catalyst for steam methane reforming (SMR) was deposited on a porous Al2O3 support using a hydrothermal-infiltration method. The SMR performance of Ni/Al2O3 composites was strongly affected by the microstructural change of the support according to the firing temperature. While there was no significant change up to 800 ℃, significant grain growth and large interfacial necking occurred after firing at 1,200 ℃, resulting in a significant increase in both porosity and pore size. The Al2O3 support with a large pore size and broad pore size distribution could load a relatively larger amount of Ni catalyst during the hydrothermal-infiltration process and facilitate the diffusion of reaction gases. Therefore, the Ni/Al2O3 composite with the support fired at 1,200 ℃ exhibited the best SMR performance. Meanwhile, Ni catalysts were distributed evenly throughout the porous support in the Ni/Al2O3 composite prepared by the hydrothermal-infiltration method compared to that prepared by the conventional infiltration method. Therefore, the Ni/Al2O3 composite prepared by the hydrothermal-infiltration method exhibited much better SMR performance. Moreover, no significant performance degradation was observed at 600 ℃ for 100 h.

A study on the Ni formation by reduction of NiO nano crystals (NiO 나노 결정의 환원 반응에 의한 Ni 형성 거동에 관한 연구)

  • Kim, Chang-Sam;Kang, Seung-Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.5
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    • pp.246-250
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    • 2009
  • The Ni formation behavior from the reduction of NiO nano crystals in the $H_2/N_2$ gas mixtures. The NiO nano crystals were synthesized by heat-treating nickel nitrate$(Ni(NO_3)_2\cdot6H_O)$ in the air at $500^{\circ}C$, and had an octahedral shape and the particle size of 200~500 nm. The NiO nano-crystals had well-developed (111) planes which is hardly formed in normal synthetic conditions. The reduction process was carried out at 300 and $600^{\circ}C$ for 15 and 60 minutes, respectively. When the NiO nano-crystals were reduced at $300^{\circ}C$, the Ni particles sustained the same octahedral shape as NiO, while Ni particles were to agglomerate at $600^{\circ}C$.

Fraccture Behavior of Recation Squeeze Cast ($AI_20_3{\cdot}SiO_2+Ni$)/Al Hybrid Metal Matrix Composites (반응 용탕단조한(AI203 . SIO2+Ni)/Al하이브리드 금속복합재료의 파괴거동 특성)

  • 김익우;김상석;박익민
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.04a
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    • pp.67-70
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    • 2000
  • Mechanical properties of (10%$AI_20_3{\cdot}SiO_2$+5%Ni)/Al hybrid composites fabricated by the reaction squeeze casting were compared with those of (15%$AI_20_3{\cdot}SiO_2$)/Al composites. Intermetallic compound formed by reaction between molten aluminum and reinforcing powder was uniformly distributed in the Al matrix. These intermetallic compounds were identified as $Al_3$NI using EDS and X-ray diffraction analysis. Microhardness and flexural strength of hybrid composites were higher than that of (15%$AI_20_3{\cdot}SiO_2$)/Al Composite. In-Situ fracture tests were Conducted on (15%$AI_20_3{\cdot}SiO_2$)/Al Composites and (10%$AI_20_3{\cdot}SiO_2$+5%Ni)/Al hybrid composites to identify the microfracture process. It was identified from the in-situ fracture test of (10%$AI_20_3{\cdot}SiO_2$+5%Ni)/Al composites, microcracks were initiated mainly at the short fiber / matrix interfaces. As the loading was continued, the crack propagated mainly along the separated interfacial regions and the well developed shear bands. It was identified from the in-situ fracture test of (10%$AI_20_3{\cdot}SiO_2$+5%Ni)/Al hybrid composites, microcracks were initiated mainly by the short fiber/matrix interfacial debonding. The crack proceeded mainly through the intermetallic compound clusters

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Effect of Ni Addition on ATiO3 (A = Ca, Sr, Ba) Perovskite Photocatalyst for Hydrogen Production from Methanol Photolysis (메탄올 광분해 수소제조를 위한 ATiO3 (A = Ca, Sr, Ba) Perovskite 광촉매의 Ni 첨가 영향)

  • Kwak, Byeong Sub;Park, No-Kuk;Lee, Tae Jin;Lee, Sang Tae;Kang, Misook
    • Clean Technology
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    • v.23 no.1
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    • pp.95-103
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    • 2017
  • In this study, $ATiO_3$ (A = Ca, Sr, Ba) perovskite, which is the widely known for non $TiO_2$ photocatalysts, were synthesized using sol-gel method. And Ni was added at the A site of $ATiO_3$ by using that it is easy to incorporate. The physicochemical characteristics of the obtained $ATiO_3$ and Ni-$ATiO_3$ particles were confirmed using the X-ray diffraction (XRD) UV-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), the $N_2$ adsorption-desorption isotherm measurement, and X-ray photoelectron spectroscopy (XPS). The $H_2$ was produced using the photolysis of MeOH. Using the Ni-$ATiO_3$ photocatalysts, $H_2$ production was higher than using the $ATiO_3$ photocatalysts. Especially, $273.84mmolg^{-1}$ $H_2$ was produced after 24 h reaction over the Ni-$SrTiO_3$. Also in the water (0.1 M KOH) with the Ni-$SrTiO_3$, $H_2$ production was $961.51mmolg^{-1}$ after 24 h reaction.

Electrochemical Properties of LiNiO$_2$/Li cell (LiNiO$_2$/Li cell의 전기화학적 특성)

  • 전대규;김철중;성창호;구할본
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.11a
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    • pp.279-282
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    • 1997
  • The propose of this study is research and improvement of LiNiO$_2$as cathode material for Lithium secondary batteries. LiNiO$_2$is prepared by heating LiOH . $H_2O$ and Ni(OH)$_2$(mole ratio 1 : 1) on various heat condition. In the result of XRD mesurement, all LiNiO$_2$prepared at this study showed hexagonal structure. In Cyclic Voltammetry, LiNiO$_2$is not conspicous about oxidation peak but oxidation curve change steeply over 3.8V and reduction peak discover at 3.6V. In discharge capacities, specific capacity is higher $O_2$than air when preliminary heated and 75$0^{\circ}C$ than $700^{\circ}C$, 80$0^{\circ}C$ when heated. Therefore, when preliminary heat at $650^{\circ}C$ $O_2$and heat at 75$0^{\circ}C$ carried out, discharge property is the best.

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Recoverty of Lithium Carbonate and Nickel from Cathode Active Material LNO(Li2NiO2) of Precursor Process Byproducts (전구체 공정부산물 LNO(Li2NiO2)계 양극활물질로부터 탄산리튬 및 니켈 회수연구)

  • Pyo, Je-Jung;Wang, Jei-Pil
    • Resources Recycling
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    • v.28 no.4
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    • pp.30-36
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    • 2019
  • In this study, Li powder was recovered from the by-product of LNO ($Li_2NiO_2$) process, which is the positive electrode active material of waste lithium ion battery, through the $CO_2$ thermal reaction process. In the process of recovering Li powder, the $CO_2$ injection amount is 300 cc/min. The $Li_2NiO_2$ award was phase-separated into the $Li_2CO_3$ phase and the NiO phase by holding at $600^{\circ}C$ for 1 min. After this, the collected sample:distilled water = 1:50 weight ratio, and after leaching, the solution was subjected to vacuum filtration to recover $Li_2CO_3$ from the solution, and the NiO powder was recovered. In order to increase the purity of Ni, it was maintained in $H_2$ atmosphere for 3 hours to reduce NiO to Ni. Through the above-mentioned steps, the purity of Li was 2290 ppm and the recovery was 92.74% from the solution, and Ni was finally produced 90.1% purity, 92.6% recovery.

Synthesis and Characterization of NiAl2O4 Inorganic Pigment Nanoparticles by a Reverse Micelle Processing (역-마이셀 공정에 의한 NiAl2O4 무기안료 나노 분말의 합성 및 특성)

  • Son, Jeong-Hun;Bae, Dong-Sik
    • Korean Journal of Materials Research
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    • v.25 no.2
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    • pp.95-99
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    • 2015
  • $NiAl_2O_4$ nanoparticle was synthesized by a reverse micelle processing for inorganic pigment. $Ni(NO_3)_2{\cdot}6H_2O$ and $Al(NO_3)_3{\cdot}9H_2O$ were used for the precursor in order to synthesize $NiAl_2O_4$ nanoparticles. The aqueous solution, which consisted of a mixing molar ratio of Ni/Al, was 1:2 and heat treated at $800{\sim}1100^{\circ}C$ for 2h. The average size and distribution of synthesized $NiAl_2O_4$ powders are in the range of 10-20 nm and narrow, respectively. The average size of the synthesized $NiAl_2O_4$ powders increased with an increasing water-to-surfactant molar ratio and heating temperature. The crystallinity of synthesized $NiAl_2O_4$ powder increased with an increasing heating temperature. The synthesized $NiAl_2O_4$ powders were characterized by X-ray diffraction analysis(XRD), a field emission scanning electron microscopy(FE-SEM), and a color spectrophotometer. The properties of synthesized powders were affected as a function such as a molar ratio and heating temperature. Results indicate that synthesis using a reverse miclle processing is a favorable process to obtain $NiAl_2O_4$ spinels at low temperatures. The procedure performed suggests that this new synthesis route for producing these oxides has the advantage of being fast and simple. Colorimetric coordinates indicate that the pigments obtained exhibit blue colors.