• 한국세라믹학회지
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• 제42권4호
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• pp.276-281
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• 2005

산소분위기, $750^{\circ}C$서 36 h 동안 하소함으로써 연소법에 의해 $LiNi_{1-y}M_{y}O_{2}(M=Zn^{2+},\;Al^{3+},\;and\;Ti^{4+},\;0.000\{\le}y{\le}0.100)$를 합성하였다. 각 시료에 대해 XRD 분석, FE-SEM 관찰, 싸이클 수에 따른 방전 용량의 변화 조사가 행해졌다. $LiNi_{0.99}M_{0.01}O_{2}$ (M=Zn, Al, and Ti) 조성이 여러 조성 중에서 대체로 우수한 전기화학적 특성을 나타내었다. 결정성과 cation mixing의 평가에서 Zn을 치환한 경우 결정성이 나쁘게 나타났고 Ti를 치환한 경우 cation mixing이 크게 나타났으며, Al을 치환한 경우 결정성이 좋고 cation mixing이 적게 나타났다. Al을 치환한 경우 싸이클 특성이 개선되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.309-310
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• 2006

In this paper, frequency characteristic of FBAR was studied as a function of annealing temperature. we have used Li dopant to enhance electrical properties of ZnO thin film. Li:ZnO thin film was deposited on Al(300 nm)/$SiO_2$(500 nm)/Si($500\;{\mu}m$) and each layer was patterned. Thermal treatment was executed in range of between 300 and $600^{\circ}C$ in $O_2$ ambient. We observed that the resistivity of ZnO is enhanced under the influence of Li doping and return loss in FBAR frequency properties is improved through annealing.

• 한국전기전자재료학회논문지
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• 제14권4호
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• pp.316-322
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• 2001

Cathode materials $LiMn_{2-y}$$M_{y}$ $O_4$(M=Zn and Mg) were obtained by reacting the mixture of LiOH.$H_2O$, Mn $O_2$ and MgO ar ZnO at 80$0^{\circ}C$ for 36h in an air atmosphere. These materials showed an extended cycle life in lithium-anode cells working at room temperatue in a 3.0 to 4.3V potential window. Among these materials, LiM $n_{1.9}$M $g_{0.1}$ $O_4$ showed the best cycle performance in terms of the capacity and cycle life. The discharge capacities of the cathode for the Li/LiM $n_{1.9}$ $M_{0.1}$ $O_4$ cell at the 1st cycle and at the 70th cycle were about 120 and 105mAh/g, respectively. This cell capacity is retained by 88% after 70th cycle. In cyclic voltammetry measurement, all cells revealed tow oxidation peaks and reduction peaks. However, Li/$LiMn_{2-y}$$M_{y}$ $O_4$ cell substituted with Zn and Mg showed new reaction peak during reduction reaction.eaction.ion.ion.

• 한국전기전자재료학회논문지
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• 제15권4호
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• pp.361-366
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• 2002

Spinel $LiMn_{2-y}M_yO_4$ and $LiMn_{2-y}M_yO_4$ (M=Mg, Zn) powders were synthesized by solid-state method at $800^{\circ}C$ for 37h. Crystal structure and electrochemical properties were analyzed by X-ray diffraction, charge-discharge test, cyclic voltammetry and ac impedance to $LiMn_{2-y}M_yO_4$. All cathode material showed spinel structure in X-ray diffraction. Ununiform distortion which calculated by (111) face and (222) face was almost constant in spite of the change of the kind and the substituting ratio of the metal cation in $LiMn_{2-y}M_yO_4$ (M=Mg, Zn). $LiMn_{1.9}Mg_{0.05}Zn_{0.05}O_4/Li$ cell substituted $Mg^{+2}$ and $Zn^{+2}$ showed excellent discharge capacities than other cells, which it presented about 120mAh/g at the 1st cycle and about 73mAh/g at the 250th cycle, respectively. AC impedance of $LiMn_{2-y}M_yO_4/Li$ cells showed the similar resistance of about 65~110$\Omega$ before cycling.

• 한국전기전자재료학회논문지
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• 제25권4호
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• pp.282-285
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• 2012

It is well known that Zinc Oxide (ZnO) is an attractive material for its various applications. ZnO has been mostly used as a transparent conducting oxide in liquid crystal displays, solar cells due to its advantages of low cost, high productivity, and excellent electrical conductivity. Notably, flexible-dye-sensitized solar cells (DSSCs) based on polyethylene terephthalate (PET) substrates require low temperature sintering processing conditions. Therefore, low temperature processing conditions have been strongly required for transparent conducting film applications. In this paper, we prepared low temperature-sintered ZnO ceramics employing Li as a sintering aid.

• 한국결정학회지
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• 제7권2호
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• pp.183-190
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• 1996

수열법을 이용하여 은(Ag)이 내장된 고온고압용 autoclave에서 KOH를 광화제로 하여 ZnO 단결정을 성장하고, LiOH 및 NH4OH의 첨가에 따른 결정외형의 변화에 대해 고찰하였다. 성장된 단결정은 연한 녹색을 띠고 있었으며 최대크기는 30×30×20mm3였다. KOH 광화제에 1.0-2.0M의 LiOH를 첨가하면 (0001)면의 flaw의 수가 감소하였다. 또한 NH4OH를 첨가한 결과 Vc/Va(c 축의 방향의 성장속도/a축 방향의 성장속도)가 증가함을 확인하였고, 이 방법을 응용하여 판상형의 종자결정 대신 침상형의 종자결정으로도 등방주상(Equant hexagonal prism)형의 ZnO 단결정을 성장할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.947-950
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• 2004

[ $ZnCr_2O_4$ ]에 $Li_2CO_3$를 $5{\sim}30wt%$ 범위에서 정량적으로 첨가한 감습재료에서 screen printing법으로 알루미나 기판 위에 후막으로 인쇄하고 $650\sim750^{\circ}C$에서 소결하여 후막 습도센서를 제작하였으며, $30\sim90%RH$ 범위에서 상대습도에 따른 저항 및 정전용량 특성을 조사하였다. $ZnCr_2O_4$에 $Li_2CO_3$가 5wt%가 첨가된 조성의 센서는 70%RH이상에서, 25wt%이상 첨가된 조성의 센서는 40%RH이하에서 저항 및 정전용량이 급격히 변화하는 switching 현상을 나타내었다. 반면, $ZnCr_2O_4$에 $Li_2CO_3$가 15wt%가 첨가된 조성의 센서는 선형적으로 저항은 감소하였고, 정전용량은 증가하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.455-458
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• 2001

Spinel $LiMn_{2-y}$$M_{y}$ $O_4$powder was prepared solid-state method by calcining the mixture of LiOH - $H_2O$, Mn $O_2$, ZnO and MgO at 80$0^{\circ}C$ for 36h. To investigate the effect of substitution with Mg, Zn cation, charge-discharge experiments and initial impedance spectroscopy performed. The structure of $LiMn_{2-y}$$M_{y}$ $O_4$crystallites was analyzed from powder X-ray diffraction data as a cubic spinel, space group Fd3m. all cathode material showed spinel phase based on cubic phase in X-ray diffraction. Ununiform which calculated by (111) face and (222) face was constant in spite of the change of y value, except PUf\ulcorner LiM $n_2$ $O_4$. The discharge capacities of the cathode for the cation subbstitUtes $LiMn_{2-y}$$M_{y}$ $O_4$/Li cell at the 1st cycle and at the 40th cycle were about 120~124 and 108~112mAh/g except LiM $n_{1.9}$Z $n_{0.1}$ $O_4$/Li cell, respectively. This cell capacity is retained by 93% after 40th cycle. AC impedance of $LiMn_{2-y}$$M_{y}$ $O_4$/Li cells revealed the similar resistance of about 65~110$\Omega$ before cycling. before cycling.g.g.

• 한국결정성장학회지
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• 제16권6호
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• pp.235-239
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• 2006

Micro-pulling down$({\mu}-PD)$법을 이용하여 직경 $0.8{\sim}1.0mm$, 길이 $30{\sim}35mm$의 ZnO가 첨가된 near-stoichiometric $LiNbO_3$, 단결정을 성장하였다. 성장된 결정의 결정구조를 powder x-tay diffraction(XRD) patterns으로 확인하였고, electron probe micro analysis(EPMA)를 이용하여 결정내 Zn 이온들이 균일하게 분포되었음을 확인하였다. 또한 2 mol% 이상의 ZnO 첨가시 $OH^-$ 흡수밴드의 특성이 크게 변화함을 관찰함으로써 ZnO 첨가량에 일치한 역치(threshold)가 존재함을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2949-2954
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• 2012

Nano ZnO with an average size of 8 nm was prepared by thermal decomposition of zinc oxalate at $450^{\circ}C$. A series of based composite polymer electrolyte PEO-$LiClO_4$ and nano ZnO as a filler have been synthesized using solution cast technique, with varying the filler ratio systematically. XRD, DSC and FTIR studies have been conducted to investigate the structure and interaction of different groups in the composite polymer electrolyte. Effect of nano ZnO ceramic filler concentration on the structure of composites and their electrical properties (DC-conductivity, AC-conductivity, dielectric constant, dielectric loss and impedance) at different frequencies and temperatures was studied. Melting temperature ($T_m$) of PEO decreased with the addition of both $LiClO_4$ salt and nano ZnO filler due to increasing the amorphous state of polymer. All composite samples showed an ionic conductivity. The maximum room temperature ionic conductivity is found for $(ZnO)_{0.5}(PEO)_{12}(LiClO_4)$ composite sample. All the results are correlated and discussed.