• 공업화학
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• 제26권5호
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• pp.521-525
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• 2015

2차원 구조와 우수한 물성을 지닌 그래핀 기반의 전극 재료들은 슈퍼커패시터에 많이 응용되어 왔다. 특히 3차원 구조의 그래핀 소재들은 전극 제조에 매우 중요한데 이는 3차원 구조가 넓은 표면적, 효과적이고 빠른 전기 및 이온 전달, 우수한 기계적 물성을 제공하기 때문이다. 최근에는 3차원 하이브리드 구조를 가지는 그래핀/금속 산화물 재료들이 슈퍼커패시터의 에너지와 파워 밀도를 동시에 증가시키고자 개발되어 왔다. 본 논문은 그래핀과 금속 산화물로 이루어진 3차원 나노복합체의 최근 연구 경향을 논하고자 한다. 3차원 나노복합체의 제조와 구조 및 이를 이용한 슈 퍼커패시터의 응용을 다룬다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.979-982
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• 2008

We studied hybrid passivation using parylene-C, metal, photoacyl and indium zinc oxide for pentacene OTFT to assure stability in subthreshold region. After the passivation, the changes in S and $V_{on}$ of OTFT were negligible and $I_{off}$ maintained its initial value of ${\sim}10^{-12}$ A. Therefore, the hybrid passivation is suitable for practical applications based on OTFT.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.252-252
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• 2014

투명전극 제조에 이용되고 있는 진공기반 ITO공정의 제조 단가를 줄이기 위하여 용액 기반의 투명전극 제조 기술에 대한 연구를 수행 하였다. 용액공정을 수행하기 위하여 ITO 나노입자를 이용한 잉크를 제조하고 이를 잉크젯 인쇄공정에 적용하여 ITO 투명전극을 제조하였다. 열처리 온도에 따른 전기적 광학적 특성에 대한 분석을 진행하였다. 전기적 물성의 극대화를 위해 Ag metal grid를 인쇄공정을 통해 제작하고 용액기반 ITO 박막과 융합화(hybridization) 시켰다. Ag metal grid의 line width를 최소화 하기 위하여 전기수력학 방식의 잉크젯 시스템을 사용하여 metal grid를 형성하였고 Ag metal grid는 약 10um의 선폭을 가졌다. 인쇄된 Ag-grid/ITO 박막의 경우 550 nm파장에서(Ag grid pitch: 500 um기준) 약88%의 투과도를 보이며 저항이 $5{\Omega}/{\square}$ 이하의 특성을 나타내었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.482-485
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• 2004

We fabricated a hybrid bulk/fully depleted silicon on insulator (FDSOI) complementary metal oxide semiconductor (CMOS) active pixel image sensor. The active pixel is comprised of reset and source follower transistors on the SOI seed wafer, while the pinned photodiode and readout gate and floating diffusion are fabricated on the SOI handle wafer after the removal of the buried oxide. The source of dark current is eliminated by hybrid bulk/FDSOI pixel structure between localized oxidation of silicon (LOCOS) and photodiode(PD). By using the low noise hybrid pixel structure, dark currents qm be suppressed significantly. The pinned photodiode can also be optimized for quantum efficiency and reduce the noise of dark current. The spectral response of the pinned photodiode on the SOI handle wafer is very flat between 400 nm and 700 nm and the dark current that is higher than desired is about 10 nA/cm2 at a $V_{DD}$ of 2 V.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.817-820
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• 2009

To meet the high current load requirement from the high energy density realized by metal oxide and high power density graphite, we propose a novel hybrid supercapacitor consisting of Nb2O5 and KS6 graphite in 1.0 M LiPF6-EC:DEC (1:2). This new system exhibits a sloping voltage profile from 2.7 to 3.5 V during charging and presents a high operating voltage plateau between 1.5 and 3.5 V during discharging. The cell was tested at a current density of 100 mA/g with a cut-off voltage between 3.0 and 1.0 V. This novel energy storage system delivers the highest initial discharge capacity of 55 mAh/g and exhibits a good cycle performance.

• 센서학회지
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• 제30권6호
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• pp.376-380
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• 2021

The accurate detection of hydrogen gas molecules is considered to be important for industrial safety. However, the selective detection of the gas using semiconductive metal oxides (SMOs)-based sensors is challenging. Here, we describe the fabrication of H₂ sensors in which a nanocellulose/graphene oxide (GO) hybrid membrane is attached to SnO₂ nanosheets (NSs). One-dimensional (1D) nanocellulose fibrils are attached to the surface of GO NSs (GONC membrane) by mixing GO and nanocellulose in a solution. The as-prepared GONC membrane is employed as a sacrificial template for SnO₂ NSs as well as a molecular sieving membrane for selective H₂ filtration. The combination of GONC membrane and SnO₂ NSs showed substantial selectivity to hydrogen gas (R_air / R_gas > 10 @ 0.8 % H₂, 100 ℃) with noise level responses to interfering gases (H₂S, CO, CH₃COCH₃, C₂H₅OH, and NO₂). These remarkable sensing results are attributed mainly to the molecular sieving effect of the GONC membrane. These results can facilitate the development of a highly selective H₂ detector using SMO sensors.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.115.1-115.1
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• 2016

Electrochemical anodization has been interested due to its useful way for the nano-scale architecture of metal oxides obtained from a metal substrate. By using this method, it is easy to control the morphology of the oxide materials by controlling electrochemical conditions. Among oxide materials obtained from the transition metals such as Ti, V, W, etc., in this paper, the morphological study of anodized $TiO_2$ was employed at various voltage conditions in fluoric based electrolyte, and the effects of applied voltage (sweep rate and retention time) on the tube morphologies were investigated. Furthermore, by using anodization of tungsten substrate (W), we fabricated the porous structure of $WO_3$ and provided merits of tailored structure for the hybridization of inorganic and organic materials as electrochromic (EC) applications. The hybrid porous $WO_3$ shows multi-chromic properties during the EC reactions at specific voltage conditions. From these results, the anodization process with tailoring nano-structure is one of the promising methods for EC applications.

• 세라미스트
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• 제22권2호
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• pp.189-197
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• 2019

Direct methanol fuel cells (DMFCs) have found a wide variety of commercial applications such as portable computer and mobile phone. In a fuel cell, the catalysts have an important role and durability and efficiency are determined by the ability of the catalyst. The activity of the catalyst is determined by the structure and shape control of the nanoparticles and the dispersion of the nanoparticles and application system. The surface energy of nanoparticles determines the activity by shape control and the nanostructure is determined by the ratio of bi- and tri-metals in the alloy and core-shell. The dispersion of nanoparticles depends on the type of support such as carbon, graphen and metal oxide. In addition, a hybrid system using both optical and electrochemical device has been developed recently.

• 한국표면공학회지
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• 제49권4호
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• pp.323-330
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• 2016

The flexible transparent conducting films (TCFs) are required to realize flexible optoelectronic devices. 1D nanomaterials such as carbon nanotubes (CNTs), metal nanowires are good candidates to replace indium tin oxide that is currently used to fabricate transparent electrode. Particularly, silver nanowires are used to produce flexible TCFs. In this review, we introduce TCF technologies based on silver nanowires/CNTs hybrid structures. CNTs can compromise drawbacks of silver nanowires for applications in high performance TCFs for optoelectronic devices.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.452-452
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• 2013

ZnO is one of the most attractive transparent conductive oxide (TCO) films because of low toxicity, a wide band gap material and relatively low cost. However, the electrical conductivity of un-doped ZnO is too high to use it as TCO films in practical application. To improve electrical properties of undoped ZnO, transition metal (TM) doped ZnO films such as Al doped ZnO or Ti doped ZnO have been extensively studied. Here, we prepared Ti doped ZnO thin films by atomic layer deposition (ALD) for the application of TCO films. ALD was used to prepare Ti-doped ZnO thin films due to its inherent merits such as large area uniformity, precise composition control in multicomponent thin films, and digital thickness controllability. Also, we demonstrated that ALD method can be utilized for fabricating highly ordered freestanding nanostructures of Ti-doped ZnO thin films by combining with BCP templates, which can potentially used in the photovoltaic applications.