• Transactions on Electrical and Electronic Materials
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• v.8 no.2
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• pp.73-78
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• 2007

The crystallization temperature in GeTe solid electrolyte films was improved by in situ-nitrogen doping by rf magnetron co-sputtering technique at room temperature. The crystallization temperature of $250\;^{\circ}C$ in electrolyte films without nitrogen doping increased by approximately $300\;^{\circ}C$, $350\;^{\circ}C$, and above $400\;^{\circ}C$ in films deposited with nitrogen/argon flow ratios of 10, 20, and 30 %, respectively. A PMC memory device with $Ge_{45}Te_{55}$ solid electrolytes deposited with nitrogen/argon flow ratios of 20 % shows reproducible memory switching characteristics based on resistive switching at threshold voltage of 1.2 V with high $R_{off}/R_{on}$ ratios. Nitrogen doping into the silver saturated GeTe electrolyte films improves the crystallization temperature of electrolyte films and does not appear to have a negative impact on the switching characteristics of PMC memory devices.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.100-101
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• 2007

Polymer thick film capacitors were successfully fabricated by using ink-jet printing and screen printing technology. First, a bottom electrode was patterned by ink-jet printing of a nano-sized silver ink. Next, a dielectric layer was formed by the screen printing, then a top electrode was pattern by ink-jet printing of a nano-sized silver ink. The printed area of the dielectric layers were changed into $2{\times}2m^2$and $4{\times}2m^2$, and also the area of the electrodes were patterned with $1{\times}1mm^2$ and $1{\times}3mm^2$. The thickness of the printed dielectric layer was ranged from 1.1 to $1.4{\mu}m$. The analysis of capacitances verified that the capacitances was proportional to the area of the printed electrode. The capacitances of the fabricated capacitors resulted in one third of the calculated capacitances.

• Nano
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• v.13 no.12
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• pp.1850145.1-1850145.8
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• 2018

In this study, a double-solvent radiation method is proposed to prepare silver nanoparticles in the pores of metal-organic framework MIL-101(Cr). The results reveal that well-dispersed silver nanoparticles with a diameter of about 2 nm were successfully fabricated in the cages of monodisperse octahedral MIL-101(Cr) with a particle size of about 400 nm. The structure of MIL-101(Cr) was not destroyed during the chemical treatment and irradiation. The resulting Ag/MIL-101 exhibits excellent catalytic performance for the reduction of 4-nitrophenol. This method can be extended to prepare other single or bimetallic components inside porous materials.

• Advances in nano research
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• v.3 no.3
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• pp.133-141
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• 2015

Influence of Ag nanoparticles on optical and photovoltaic properties of, silicon substrates, silicon solar cells and glass have been investigated. Silver nanoparticles have been fabricated by evaporation of thin Ag layers followed by the thermal annealing. The surface plasmon resonance peak was observed in the absorbance spectrum at 470 nm of glass with deposited silver nanoparticles. It is demonstrated that deposition of silver nanoparticles on silicon substrates was accompanied with a significant decrease in reflectance at the wavelength 360-1100 nm and increase of the absorption at wavelengths close to the band gap for Si substrates. We studied influence of Ag nanoparticles on photovoltaic characteristics of silicon solar cells without and with common use antireflection coating (ARC). It is shown that silver nanoparticles deposited onto the front surface of the solar cells without ARC led to increase in the photocurrent density by 39% comparing to cells without Ag nanoparticles. Contrary to this, solar cells with Ag nanoparticles deposited on front surface with ARC discovered decrease in photocurrent density. The improved performance of investigated cells was attributed to Ag-plasmonic excitations that reduce the reflectance from the silicon surface and ultimately leads to the enhanced light absorption in the cell. This study showed possibility of application of Ag nanoparticles for the improvement of the conversion efficiency of waferbased silicon solar cells instead of usual ARC.

• Applied Chemistry for Engineering
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• v.33 no.6
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• pp.574-580
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• 2022

While in the process of electroless plating of dendrite-shape copper with silver, various silver-coated copper (Ag@Cu) particles were prepared by using both displacement plating and reducing electroless plating. The physicochemical properties of Ag@Cu particles were analyzed by scanning electron microscope- energy-dispersive X-ray spectroscopy (SEM-EDS), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Brunauer-Emmett-Teller analysis (BET), and it was confirmed that the silver coated by the reducing electroless plating was formed as nano-particles on the copper surface. Ag@Cu particles were compounded with an epoxy resin to prepare a conductive film, and its thermal stability was evaluated. We investigated the effect of the difference between the displacement plating and reducing electroless plating on the initial resistance and thermal stability of conductive films.

• Journal of the Korean Electrochemical Society
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• v.6 no.2
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• pp.103-112
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• 2003

Various kinds of metals were coated on synthetic graphite in order to investigate the relationship between film characteristics and their electrochemical performance. Gas suspension spray coating method was employed for the coating of synthetic graphite. In our experimental range, all of the metal coated synthetic graphite showed the higher capacity than that of raw material at high C-rate mainly due to decrease in impedance of passivation film. In cyclic voltammetry experiments, silver-coated and tin-coated graphite anodes found the lithium-alloy reaction. Considering smaller amount of metal coating, the most increase in discharge capacity was caused by improvement of conductivity of the electrode. When single-component metal was coated, silver-coated graphite anode exhibited the highest discharge capacity and better cycleability. Double components of silver-nickel coated active material showed the highest discharge capacity, rate capability and the best cycle performance in the range of our experiments.

• Journal of the Korean Ceramic Society
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• v.44 no.4 s.299
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• pp.208-213
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• 2007

Alumina/silver ($Al_2O_3/Ag$) nanocomposites with Ag content up to 9 vol% were prepared from nanopowder by soaking method using ${\gamma}-Al_2O_3$ of needle type and spark plasma sintering (SPS). The mechanical properties of specimens were investigated three-point flexural strength and toughness as a function of the Ag contents. The maximum flexural strength of the alumina/silver nanocomposite was 850 MPa for the 1 vol% composite, and also higher than monolith alumina as about 800 MPa at 3, 5, and 7 vol% Ag contents. Fracture toughness by single edged V-notch beam (SEVNB) was $4.05MPa{\cdot}m^{1/2}$ for the 3 vol% composite and maintained about $4.00MPa{\cdot}m^{1/2}$ at 5, and 7 vol% Ag content. Microstructure of fracture surface for each fracture specimens was observed. Due to the inhibition effect of alumina grain growth, the average grain size of nanocomposites depends on the content of Ag nano particles. The fracture morphology of nanocomposite with dislocation (sub-grain boundary) by silver nano-particles of second phases in the alumina matrix also showed transgranular fracture-mode compare with intergranular of monolith alumina. Thermal conductivity of specimens at room temperature was about 40 W/mK for the 1 vol% Ag content.

• Nano
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• v.13 no.12
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• pp.1850146.1-1850146.9
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• 2018

The rapid development of smart textiles requires the large-scale fabrication of conductive fibers. In this study, we develop a simple, scalable and low-cost capillary-driven self-assembly method to prepare conductive fibers with uniform morphology, high conductivity and good mechanical strength. Fiber-shaped flexible and stretchable conductors are obtained by coating highly conductive and flexible silver nanowires (Ag NWs) on the surfaces of yarn and PDMS fibers through evaporation-induced flow and capillary-driven self-assembly, which is proven by the in situ optical microscopic observation. The density of Ag NWs and linear resistance of the conductive fibers could be regulated by tuning the assembly cycles. A linear resistance of $1.4{\Omega}/cm$ could be achieved for the Ag NWs-coated nylon, which increases only 8% after 200 bending cycle, demonstrating high flexibility and mechanical stability. The flexible and stretchable conductive fibers have great potential for the application in wearable devices.

• Journal of the Korean Applied Science and Technology
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• v.38 no.6
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• pp.1553-1560
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• 2021

We have confirmed that optimized transmittance and surface resistance by electrospinning time, also the fabricated transparent electrode composed of silver nanofiber with excellent electrical, optical and mechanical performances is showed applicability to next generation flexible displays such as solar cells, displays, and touch screens. → We have confirmed the optimized transmittance and surface resistance by electrospinning time Also the fabricated transparent electrode composed of silver nanofiber with excellent electrical, optical and mechanical performances showed applicability to next generation flexible displays such as solar cells, displays, and touch screens.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1594-1597
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• 2008

Carbon nanotube (CNT) cathodes were fabricated using nano-sized silver powders as a bonding material. The effects of powder size on the field emission properties for the CNT cathode were investigated The better emission properties of CNT cathodes using smaller particles are due to a low sintering temperature of the bonding materials.