We have demonstrated the production of thin films containing multilayer graphene-coated copper nanoparticles (MGCNs) by a commercial electrodeposition method. The MGCNs were produced by electrical wire explosion, an easily applied technique for creating hybrid metal nanoparticles. The nanoparticles had average diameters of 10–120 nm and quasi-spherical morphologies. We made a complex-electrodeposited copper thin film (CETF) with a thickness of 4.8 μm by adding 300 ppm MGCNs to the electrolyte solution and performing electrodeposition. We measured the electric properties and performed corrosion testing of the CETF. Raman spectroscopy was used to measure the bonding characteristics and estimate the number of layers in the graphene films. The resistivity of the bare-electrodeposited copper thin film (BETF) was 2.092 × 10–6 Ω·cm, and the resistivity of the CETF after the addition of 300 ppm MGCNs was decreased by 2% to ~2.049 × 10–6 Ω·cm. The corrosion resistance of the BETF was 9.306 Ω, while that of the CETF was increased to 20.04 Ω. Therefore, the CETF with MGCNs can be used in interconnection circuits for printed circuit boards or semiconductor devices on the basis of its low resistivity and high corrosion resistance.

In this study, simple chemical synthesis of green emitting Cd-free InP/ZnS QDs is accomplished by reacting In, P, Zn, and S precursors by one-pot process. The particle size and the optical properties were tailored, by controlling various experimental conditions, including [In]/[MA] (MA: myristic acid) mole ratio, reaction temperature and reaction time. The results of ultraviolet–visible spectroscopy (UV-vis), and of photoluminescence (PL), reveal that the exciton emission of InP was improved by surface coating, with a layer of ZnS. We report the correlation between each experimental condition and the luminescent properties of InP/ZnS core/shell QDs. Transmission electron microscopy (TEM), and X-ray powder diffraction (XRD) techniques were used to characterize the as-synthesized QDs. In contrast to core nanoparticles, InP/ZnS core/shell treated with surface coating shows a clear ultraviolet peak. Besides this work, we need to study what clearly determines the shell kinetic growth mechanism of InP/ZnS core shell QDs.

The sol-gel method is the simplest method for synthesizing monodispersed silica particles. The purpose of this study is to synthesize uniform, monodisperse spherical silica nanoparticles using tetraethylorthosilicate (TEOS) as the silica precursor, ethanol, and deionized water in the presence of ammonia as a catalyst. The reaction time and temperature and the concentration of the reactants are controlled to investigate the effect of the reaction parameters on the size of the synthesized particles. The size and morphology of the obtained silica particles are investigated using transmission electron microscopy and particle size analysis. The results show that monodispersed silica particles over a size range of 54-504 nm are successfully synthesized by the sol-gel method without using any additional process. The nanosized silica particles can be synthesized at higher TEOS/H2O ratios, lower ammonia concentrations, and especially, higher reaction temperatures.

Polyethersulfone (PES) 고분자 상변환막의 성능을 향상시키기 위해 PES 고분자에 나노 크기의 ZnO 무기입자를 함침시킨 혼합기질막(mixed matrix membrane)을 제조하고 특성을 평가하였다. PES-ZnO 혼합기질막은 ZnO 나노입자를 PES 대비 최대 0.375 wt%의 낮은 비율로 첨가시킨 PES-ZnO-NMP(N-methyl-1-pyrrolidone)로 이루어진 캐스팅 용액을 사용하여 상변환법을 통해 제조하였다. 제조된 혼합기질 막의 물성과 특성은 막의 단면구조 관찰, 접촉각 측정, 인장강도 측정, 순수 투과량 측정 및 BSA 단백질 용액의 한외여과 실험을 통해 평가하였다. 이 결과 혼합기질 막은 PES 고분자 matrix에 함유된 ZnO 나노입자로 인해 막의 친수성이 증가하여 막오염 발생이 억제되어 투과량이 증가하였다. ZnO 나노입자는 혼합기질막의 제조에 있어 막오염의 발생 억제와 투과량 증가에 유용하게 사용될 수 있는 무기물 첨가제임을 알 수 있다.

Ni nanoparticles (NPs)-graphitic carbon nanofiber (GCNF) composites were fabricated using an electrospinning method. The amounts of Ni precursor used as catalyst for the catalytic graphitization were controlled at 0, 2, 5, and 8 wt% to improve the photovoltaic performances of the nanoparticles and make them suitable for use as counter electrodes for dyesensitized solar cells (DSSCs). As a result, Ni NPs-GCNF composites that were fabricated with 8 wt% Ni precursors showed a high circuit voltage (0.73 V), high photocurrent density (14.26 mA/cm2), and superb power-conversion efficiency (6.72 %) when compared to those characteristics of other samples. These performance improvements can be attributed to the reduced charge transport resistance that results from the synergetic effect of the superior catalytic activity of Ni NPs and the efficient charge transfer due to the formation of GCNF with high electrical conductivity. Thus, Ni NPs-GCNF composites may be used as promising counter electrodes in DSSCs.

Ni nanoparticles (NPs)-graphitic carbon nanofiber (GCNF) composites were fabricated using an electrospinning method. The amounts of Ni precursor used as catalyst for the catalytic graphitization were controlled at 0, 2, 5, and 8 wt% to improve the photovoltaic performances of the nanoparticles and make them suitable for use as counter electrodes for dyesensitized solar cells (DSSCs). As a result, Ni NPs-GCNF composites that were fabricated with 8 wt% Ni precursors showed a high circuit voltage (0.73 V), high photocurrent density (14.26 mA/cm2), and superb power-conversion efficiency (6.72 %) when compared to those characteristics of other samples. These performance improvements can be attributed to the reduced charge transport resistance that results from the synergetic effect of the superior catalytic activity of Ni NPs and the efficient charge transfer due to the formation of GCNF with high electrical conductivity. Thus, Ni NPs-GCNF composites may be used as promising counter electrodes in DSSCs.

PEBAX®는 폴리에테르가 우수한 CO2용해도를 나타내어 기체분리막의 소재로 주목받고 있지만 폴리아마이드의 crystallinity로 인해 투과성능면에서 제약을 받는다고 알려져 있다. 본 연구에서는 PEBAX® 막의 기체투과특성을 향상시키기 위해 합성된 aluminosilicate hollow nanoparticles를 막 내부에 고르게 분산시켜 함량별로 혼합막을 제조한다. 분산된 나노입자의 함량에 따른 CO2 용해도 증가, 확산 속도의 증가로 인하여 선택도와 투과도의 향상을 예측할 수 있다. 첨가된 나노입자의 morphology와 yield를 확인하고, 첨가량이 증가할수록 선택도의 변동없이 투과도가 증가하는 것을 알 수 있다.

Facilitated transport membranes in the solid state have been attractive because they can improve both the permeability and the selectivity simultaneously to overcome the trade-off behavior. The carrier activity for facilitated transport plays a key role in determining separation performance. We have reported the solid-state facilitated transport membranes containing surface-activated Ag nanoparticles (NPs) as an olefin carrier for separation of olefin/paraffin mixtures, particularly propylene/propane mixture. Interestingly, the surface positive charge density of Ag atom in Ag NPs was linearly correlated with the propylene solubility and also with the propylene/propane selectivity. In addition, the separation performance has been maintained unchanged up to 500 hours.

Noncontact direct-printed conductive silver patterns with an enhanced electrical resistivity are fabricated using a silver ink with a mixture of silver nanoparticles and nanoplates. The microstructure and electrical resistivity of the silver pattern are systematically investigated as a function of the mixing ratio of the nanoparticles and nanoplates. The pattern, which is fabricated using a mixture with a mixing ratio of 3(nanoparticles):7(nanoplates) and sintered at 200oC shows a highly dense and well-sintered microstructure and has a resistivity of 7.60 μΩ·cm. This originates a mutual synergistic effect through a combination of the sinterability of the nanoparticles and the packing ability of the nanoplates. This is a conductive material that can be used to fabricate noncontact direct-printed conductive patterns with excellent electrical conductivity for various flexible electronics applications, including solar cells, displays, RFIDs, and sensors.

Soybean peptide (SP) exhibited low intestinal absorption at oral administration due to its fragile structure under gastric digestion. Therefore, we have attempted to encapsulate peptide by cross-linkage interaction between positive charged chitosan (CS) or chitosan oligosaccharide (CSO) and negative charged peptide. The CS (or CSO) with SP nanoparticles were prepared by using ultrasonification technique. The objective of this study was to find the optimal processing method by changing concentration, pH, and homogenizing conditions. We measured physicochemical properties such as particle size, zeta-potential, encapsulation efficiency (EE%), release rate (RR) and antioxidant ability of samples. The results showed that the optimal processing method was using 0.5% (w/v) CSO (diluted by pH 3 Acetic acid buffer) mixed with 0.5% (w/v) SP (diluted by pH 6 buffer) by 9:1 ratio. Afterwards, using high-speed mixer at 12,000 rpm for 3 min, and then passed 2 times through an ultrasonicator (50% power, 3 min). In this way for processing, the particle sizes of CSO/SP nanoparticles were approximately 300 nm, zeta-potential were approximately 45 mV. In addition, the EE% and RR of CS/SP nanoparticles was higher than the CSO/SP nanoparticles. The increase in antioxidant ability of SP was attributed to the affected by CS/CSO microcapsules. In conclusion, this research can befoundation for the manufacturing process of CS/SP nanoparticles, and it was expected that the future application of this nanoparticle in food matrix.

A novel nanocomposite LDPE film with UV protective properties was developed for active packaging applications. Initially, undoped and Mn-doped TiO2 nanoparticles (NPs) were synthesized by the sol-gel method and the resulting particles were characterized. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images revealed an agglomerated nature and spherical morphology. X-ray diffraction (XRD) studies indicated that all products were crystalline and in the form of rutile. The reflectance spectrum of undoped TiO2 NPs demonstrated a characteristic sharp edge at 410 nm. Subsequently, nanocomposite (NC) LDPE samples were prepared with the NPs by solvent precipitation followed by film casting. The optical and thermal properties of the NC samples were investigated. Incremental increases in Mn concentration from 0.25 mol % to 1.00 mol % were associated with progressive decreases in light transmission in the UV region. The melting and maximum decomposition temperatures of all NCs were 107 and 442-449 °C, respectively. The UV protective LDPE-based NC films exhibited superior photostability. Absorption in the FTIR spectra at 1716 and 1734 cm-1 changed after 4-wk exposure to UV for all film samples as a consequence of photodegradation. Finally, the photooxidation of perilla oil was assessed as an example of a UV protective packaging application. After 12 days, protection with 1.00 mol% Mn-doped TiO2-LDPE was associated with a gradual increase in PV, while protection with TiO2-LDPE was associated with a significant increase and protection with the control treatment was associated with a dramatic increase in PV. Hence, a 1.00 mol% Mn-doped TiO2-LDPE NC showed promise for UV shielding packaging applications.

The aim of this study was to improve dispersion stability of calcium carbonate (CaCO3) nanoparticles in aqueous medium using alkyl polyglucoside (APG). One hundred milligrams of CaCO3 nanoparticles was mixed with 30 mL of deionized water. Thereafter, APG was dissolved into the CaCO3 nanoparticle mixtures at approximate 0, 0.1, 0.3, 0.5, 0.7, and 0.9%, and subsequently, pH was adjusted to 7.0 and 10.0. Afterward, all CaCO3 nanoparticle mixtures were dispersed by ultrasonic processing treatment for 10 min. Dispersion stability and physicochemical properties of the CaCO3 nanoparticle mixtures were observed by measuring the change of absorbance and mean diameter for 96 h as well as the initial zeta-potential. As results, initial zeta-potentials of the CaCO3 nanoparticles in deionized water at pH 7.0 and 10.0 showed approximately +20 and 0, respectively. The positive surface charge at pH 7.0 had unfavorable impact on the adsorption of APG onto CaCO3 nanoparticles in the aqueous suspensions because APG is nonionic surfactant. Among all samples at pH 10, CaCO3 nanoparticles in 0.5% APG aqueous solution showed the smallest initial mean diameter and the slowest increase in mean diameter and decrease in absorbance. In conclusion, the pH 10.0 and 0.5% APG concentration was the most desirable condition in order to improve dispersion stability of CaCO3 nanoparticles in an aqueous medium.

Colorectal cancer is one of the most common types of cancer in men and women who consume a Western diet. We investigated the inhibitory effect of selenium (sodium selenite, Na2SeO3) and selenium nanoparticles (nano-Se) on experimental colon carcinogenesis in ICR mice. After a 1-week acclimation, 6-week-old mice received three intraperitoneal (i.p.) injections (experimental week 0-2) of azoxymethane (AOM, 10 mg/kg body weight, b.w.), followed by 2% dextran sodium sulfate (DSS)-containing drinking water for the next 1 week. The three groups (10 mice/group) were orally administered either distilled water (control), selenium (1.7 ppm), or nano-Se (1.7 ppm) daily for 8 weeks. The numbers of aberrant crypt foci (ACF), aberrant crypt (AC), and tumorous lesions were measured in colonic mucosa. Se and nano-Se treatments significantly decreased the number of ACF, AC, and tumorous lesions compared with the control. However, there was no significant difference between the selenium and nano-Se groups. The glutathione peroxidase (GSH-Px) activity in the liver and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity in serum, were high in the selenium and nano-Se groups, while thiobarbituric acid reactive substance (TBARS) level was low in both Se and nano-Se groups when compared with that in the control group. These findings indicate that selenium and nano-Se showed similar protective effects against colon carcinogenesis by inhibiting the development of ACF and tumorous lesions in mice.

Pollutants removal and disinfection effect of secondary effluent from final settling tank of sewage treatment plant of W city were investigated in Loop Reactor using ordinary granular activated carbon(GAC) and GAC coated with silver nanoparticles. The results showed that the removal efficiency of CODMn, T-N and T-P using GAC with silver nanoparticles were higher than using the ordinary GAC. The removal efficiency of T-P using GAC with silver nanoparticles is 45.4% and that of T-P using ordinary GAC is 30.9% in the same case of the input amount of 20 g/L of GAC. The total califorms is reduced according to increasing input amount of GAC with silver nanoparticles and ordinary GAC. The disinfection efficiency of total coliforms in case of GAC with silver nanoparticles is much higher than that in case of ordinary GAC. For all experiments using the silver nanoparticles, the total coliforms is under 26 cfu/mL and this shows very excellent disinfection effect.

Copper nanoparticles attract much attention as substitutes of noble metals such as silver and can help reduce the manufacturing cost of electronic products due to their lower cost and good conductivity. In the present work, the chemical reduction is examined to optimize the synthesis of nano-sized copper particles from copper sulfate. Sodium borohydride and ascorbic acid are used as reducing and antioxidant agents, respectively. Polyethylene glycol (PEG) is used as a size-control and capping agent. An appropriate dose of PEG inhibits the abnormal growth of copper nanoparticles, maintaining chemical stability. The addition of ascorbic acid prevents the oxidation of nanoparticles during synthesis and storage. Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) are used to investigate the size of the synthesized nanoparticles and the coordination between copper nanoparticles and PEG. For chemical reduction, copper nanoparticles less than 100 nm in size without oxidized layers are successfully obtained by the present method.

Fluorine-doped tin oxide (FTO) nanoparticles have been successfully synthesized using ultrasonic spray pyrolysis. The morphologies, crystal structures, chemical bonding states, and electrochemical properties of the nanoparticles are investigated. The FTO nanoparticles show uniform morphology and size distribution in the range of 6-10 nm. The FTO nanoparticles exhibit excellent electrochemical performance with high discharge specific capacity and good cycling stability (620mA h g−1 capacity retention up to 50 cycles), as well as excellent high-rate performance (250 mA h g−1 at 700mAg−1) compared to that of commercial SnO2. The improved electrochemical performance can be explained by two main effects. First, the excellent cycling stability with high discharge capacity is attributed to the nano-sized FTO particles, which are related to the increased electrochemical active area between the electrode and electrolyte. Second, the superb high-rate performance and the excellent cycling stability are ascribed to the increased electrical conductivity, which results from the introduction of fluorine doping in SnO2. This noble electrode structure can provide powerful potential anode materials for high-performance lithiumion batteries.

제조나노물질의 발전으로 이를 이용한 제품들이 늘어남에 따라 상수 내 나노 물질에 대한 잠재 위해성 논란이 제기되어 왔다. 응집과 같은 기존 나노물질 처리 방법에 비해 막 분리법은 2차 오염물이 없고 재사용이 가능하기 때문에 각광받고 있다. 하지만 수계환경 변화로 인한 나노물질의 특성변화에 따른 막 기 반 공정 내 나노물질 거동에 대한 연구는 미미한 실정이다. 따라서 본 연구에서 는 국내에서 사용되고 있는 대표 제조나노물질인 Ag, ZnO, TiO2의 수계 내 유 기물 존재여부에 따른 특성을 분석하고 막기반 상수처리 공정에서의 거동을 평가하고자 하였다. SR-NOM을 대표 자연유기물로 평가하였으며 상수 내 SR-NOM의 유/무에 따른 나노물질들의 응집성 등의 변화가 막기반 공정 결과에 영향을 주었음을 확인하였다.

Facilitated olefin transport membrane, containing positively charged silver nanoparticles (AgNPs) as olefin carriers dispersed in poly(vinyl pyrrolidone) (PVP), leads extremely high separation performances for propylene/propane mixtures. In this study, as representatives of electron withdrawing nitrobenzene compounds, 1,2-dinitrobenzene (DNB) and 3,4-dinitro toluene (DNT) were used for PVP/AgNPs membranes. The correlation between the surface charge density of AgNPs and the separation performance was investigated with X-ray photoelectron spectroscopy (XPS). A fairly good linear correlation between the surface charge density and the separation performance was confirmed, which meant that the positive charge density on the surface of AgNPs may be a key factor in determining the separation performance of facilitated olefin transport membranes.