• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.166-166
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• 2013

Mesoporous $SiO_2$-supported Ni catalysts (Ni/$SiO_2$ and Ni/$TiO_2$/$SiO_2$) were fabricated by atomic layer deposition (ALD), and their catalytic activity and stability were investigated in carbon dioxide reforming of methane (CRM) reaction at $800^{\circ}C$ The Ni/$SiO_2$ catalysts showed high stability as a result of confinement of Ni particles with a mean size of ~10 nm within the pores of $SiO_2$ support. Besides, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM) results showed that the Ni nanoparticles were partially buried inside the $SiO_2$ support. The strong interaction between Ni and the $SiO_2$ support could also be advantageous for long-term stability of the catalyst. In case of the Ni/$TiO_2$/$SiO_2$ catalyst, it was found that the catalytic activity of 10 nm-sized Ni nanoparticles was not much influenced by $TiO_2$ addition.

• 한국분말재료학회지
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• 제21권4호
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• pp.286-293
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• 2014

The electrochemical properties of cells assembled with the $LiNiO_2$ (LNO) recycled from cathode materials of waste lithium secondary batteries ($Li[Ni,Co,Mn]O_2$), were evaluated in this study. The leaching, neutralization and solvent extraction process were applied to produce high-purity $NiSO_4$ solution from waste lithium secondary batteries. High-purity NiO powder was then fabricated by the heat-treatment and mixing of the $NiSO_4$ solution and $H_2C_2O_4$. Finally, $LiNiO_2$ as a cathode material for lithium ion secondary batteries was synthesized by heat treatment and mixing of the NiO and $Li_2CO_3$ powders. We assembled the cells using the $LiNiO_2$ powders and evaluated the electrochemical properties. Subsequently, we evaluated the recycling possibility of the cathode materials for waste lithium secondary battery using the processes applied in this work.

• 한국세라믹학회지
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• 제30권11호
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• pp.949-954
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• 1993

Microstructural development at the ZrO2/NiTi bonding interface and reaction products were examined and identified with SEM and AEM. Ti-oxide, Ti2Ni and Ni2Ti layer were observed whose thickness depends on bonding temperature typically. The development of Ti-oxide layer is related with oxygen ion in ZrO2 and liquid phase Ti2Ni. It is considered that compositional deviation from homogeneity and residual stress caused by thermal expansion mismatch are closely related with the formation of the Ti2Ni phase.

• 한국수소및신에너지학회논문집
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• 제10권3호
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• pp.177-184
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• 1999

The charge-discharge characteristics of the $Mg_2Ni-x$ wt.%Nd (x = 0~3) electrodes were investigated. The electrodes were prepared by the mechanical grinding of the induction-melted $Mg_2Ni$ alloy powders with Ni and/or Nd using planetary ball mill apparatus. The discharge capacity of the $Mg_2Ni$ alloy increased with the increase in the nickel content. The electrode possessing 100 wt.% nickel powder showed the initial capacity of 760 mAh/g and the capacity decay with the cycle number was less than that of the 55 wt.% nickel powder. The Nd was added to this composition. It was found that the $Mg_2Ni-100$ wt.%Ni -0.2 wt.%Nd alloy showed an excellent charge-discharge cycle characteristics compared with the other reported Mg-Ni alloy system. The discharge capacity was 400 mAh/g after 70 cycles. Such an improved cycle life seems to be attributed to the improvement in the corrosion characteristics of the alloy. The anodic polarization curve of the $Mg_2Ni-100$ wt.%Ni-0.2 wt.%Nd alloy exhibited better passivating behavior than that of the $Mg_2Ni-100$ wt.%Ni.

• 반도체디스플레이기술학회지
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• 제6권4호
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• pp.65-68
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• 2007

An epitaxial NiSi structure on Si (001) substrate was studied by using density functional theory (DFT). Orhorhombic and B2-NiSi structures were compared first. B2 structure was further considered as it has same crystal structure as Si and the lattice mismatch between B2 and Si is small, compared to orthorhombic-NiSi. The lattice parameters of x- and y-direction in B2-NiSi structure were modified to match with those in Si (001). The size reduction of the lattice parameter of B2-NiSi to match with that of Si increased the lattice parameter of z-direction by 10.5%. Therefore, we propose that an optimum structure of NiSi for epitaxial growth on Si (001) is a tetragonal structure.

• 한국재료학회지
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• 제18권9호
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• pp.482-485
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• 2008

Tetragonal-$Ni_{1-x}Pd_x$Si/Si (001) structure was studied by using density functional theory (DFT). An epitaxial interface between $2{\times}2{\times}4$ (001) tetragonal-NiSi supercell and $1{\times}1{\times}2$ (001) Si supercell was first constructed by adjusting the lattice parameters of B2-NiSi structure to match those of the Si structure. We chose Ni atoms as a terminating layer of the B2-NiSi; the equilibrium gap between the tetragonal-NiSi and Si was calculated to be 1.1 ${\AA}$. The Ni atoms in the structure moved away from the original positions along the z-direction in a systematic way during the energy minimization. Two different Ni sites were identified at the interface and the bulk, respectively. The two Ni sites at the interface have 6 and 7 coordination numbers. The Ni sites with coordination number 6 at the interface were located farther away from the interface, and were more favorable for Pd substitution.

• 한국세라믹학회지
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• 제41권2호
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• pp.106-110
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• 2004

NiO 산화물 타겟을 이용한 RF 마그네트론 스퍼터로 상온에서 Si(100) 기판 위에 NiO 박막을 증착시켜, 스퍼터 가스의 산소 유량비가 NiO 박막의 결정 배향성과 표면 형상에 미치는 영향을 조사하였다. Ar 가스에서 증착된 NiO 박막은 높은결정화도와 (100)면의 우선 배향성을 나타내었으나, $O_2$ 가스에서 증착된 경우에는 (111)면의 우선 배향성을 보였으며 그 증착속도도 감소하였다. 스퍼터 가스의 $O_2$ 함량에 따른 NiO 박막의 결정성과 우선배향성 변화에 대한 요인을 고찰하였으며, 박막의 표면 형상과 거칠기의 변화를 조사하였다.

• 한국수소및신에너지학회논문집
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• 제10권1호
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• pp.49-57
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• 1999

In order to study the effect of high energy ball milling on the $Mg_2Ni+Ni$, $Mg_2Ni+0.5Ni+0.5Al$ powders, we have investigated on the discharge properties, microstructures. The powder size of samples decreased as ball milling time. From the XRD results, the crystal structure of $Mg_2Ni+Ni$ mixed powders were changed to amorphous or nano-structure after 60hr ball milling. The discharge capacities of both $Mg_2Ni+Ni$ and $Mg_2Ni+0.5Ni+0.5Al$ powders increased, with increasing ballmilling time, the maximum capacity(342mAh/g) was shown for the 60 hrs ballmilled $Mg_2Ni+Ni$ sample. The capacity decreased drastically after a few charge-discharge cycles.

• 공업화학
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• 제30권6호
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• pp.757-761
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• 2019

고정층 상압 유통식 반응기를 사용하여 M(1)-Ni(5)/AlCeO₃ (M = La, Ce, Y) 촉매상에서 메탄의 부분 산화 반응을 수행하여 수소의 수율을 조사하였다. XRD 분석으로 반응 전과 반응 후의 환원된 La(1)-Ni(5)/AlCeO₃ 촉매의 결정상 특성피크를 조사하였고 FESEM과 EDS 분석으로 La, Ni, Ce 금속 입자가 촉매 표면상에 균일하게 분포하고 있음을 조사하였다. XPS 분석으로 촉매 표면상에 O^2-, O₂^2-의 산소와 Ce³⁺, Ce⁴+, La³⁺, Ni²⁺ 등의 이온이 존재함을 알 수 있었고, Ni(5)/AlCeO₃ 촉매에 1 wt%의 La를 첨가하면 Ni2p_3/2과 Ce3d_5/2의 원자가 각각 52.7과 6.3%로 증가하였다. La(1)-Ni(5)/AlCeO₃ 촉매상에서 수소의 수율은 89.1%이었으며, M(1)-Ni(5)/AlCeO₃ (M = Ce, Y)보다 매우 우수하였다. AlCeO₃이 산소와 반응하여 만들어진 CeO₂의 Ce⁴⁺ 이온이 La³⁺로 치환됨으로서 격자에 산소 빈자리를 만들고 strong metal-support interaction (SMSI) 효과로 Ni 원자의 분산을 증가시켜 수소 수율를 향상시켰다.

• 열처리공학회지
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• 제14권1호
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• pp.1-7
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• 2001

A method to simultaneously synthesize and consolidate the silicide $NiSi_2$ and the composite $NiSi_2$-20vol.%Nb from powders of Ni, Si, and Nb was investigated. Combustion synthesis was carried out under the combined effect of an electric field and mechanical pressure. The final density of the products increased nearly linearly with the applied pressure. Highly dense $NiSi_2$ and $NiSi_2$-20vol.%Nb with relative densities of up to 97% were produced under the simultaneous application of a 60MPa pressure and a 3000A current on the reactant powders. The respective Vickers microhardness values for these materials were 6.0 and 5.8 GPa. From indentation crack measurements, the fracture toughness values for $NiSi_2$ and $NiSi_2$-20vol.%Nb were calculated to be 3.3 and 4.7 $MPa{\cdot}m^{1/2}$, respectively.