• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.18.2-18.2
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• 2011

We study and analyze here a novel and simple approach to produce copper oxide nanowires in a methanol as an alternative to chemical synthesis routs and VLS-growth method. First, copper oxide nanowires are grown from copper nanoparticles in methanol at $60^{\circ}C$. Nanoparticles are synthesized via inert gas condensation, one of the dry processes. Synthesized nanowires were confirmed via XRD, FESEM and TEM. As a result, all particles have grown to Cu2O nanowires (20~30 nm in diameter, 5~10 um in length; aspect ratio >160~500). Next, these synthesized oxide nanowires are reduced copper nanowires in the furnace under hydrogen flow at $200{\sim}450^{\circ}C$. The evolution of oxide nanowires and their transformation to copper nanowires is studied as a function of time.

• Membrane and Water Treatment
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• v.9 no.6
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• pp.481-487
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• 2018

Membrane clogging or fouling of the membrane caused by organic, inorganic, and biological on the surface is one of the main obstacles to achieve high flux over a long period of the membrane filtration process. So researchers have been many attempts to reduce membrane fouling and found that there is a close relationship between membrane surface hydrophilicity and membrane fouling, such that the same conditions, a greater hydrophilicity were less prone to fouling. Nanotechnology in the past decade is provided numerous opportunities to examine the effects of metal nanoparticles on the both hydrophilic and antibacterial properties of the membrane. In the present study the improvement of hydrophilic and antimicrobial properties of the membrane was evaluated by adding nanoparticles of titanium dioxide and copper oxide. For this purpose, 4% copper oxide and titanium dioxide nanoparticles with a ratio of 0, 30, 50, and 70% of copper oxide added to the polymeric membrane and compare to the pure polymeric membrane. Comparison experiments were performed on E. coli PTCC1998 in two ways disc and tube and also to evaluate membrane hydrophilic by measuring the contact angle and diameter of pores and analysis point SEM has been made. The results show that the membrane-containing nanoparticle has antibacterial properties and its impact by increasing the percentage of copper oxide nanoparticles increases.

• Journal of Powder Materials
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• v.17 no.4
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• pp.276-280
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• 2010

In the present work, ethylene glycol-based (EG) copper oxide nanofluids were synthesized by pulsed wire evaporation method. In order to explode the pure copper wire, high voltage of 23 kV was applied to the both ends of wire and argon/oxygen gas mixture was used as reactant gas. EG-based copper oxide nanofluids with different volume fraction were prepared by controlling explosion number of copper wire. From the transmission electron microscope (TEM) image, it was found that the copper oxide nanoparticles exhibited an average diameter about 100 nm with the oxide layer of 2~3 nm. The synthesized copper oxide consists of CuO/$Cu_2O$ phases and the Brunauer Emmett Teller (BET) surface area was estimated to be $6.86\;m^2\;g^{-1}$. From the analyses of thermal properties, it is suggested that viscosity and thermal conductivity of EG-based copper oxide nanofluids do not show temperature-dependent behavior over the range of 20 to $90^{\circ}C$. On the other hand, the viscosity and thermal conductivity of EG-based copper oxide nanofluids increase with volume fraction due to the active Brownian motion of the nanoparticles, i.e., nanoconvection.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.855-859
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• 2023

Copper oxide (CuO) nanoparticles were successfully synthesized using a precursor in which industrial starch was impregnated with an aqueous solution of copper (II) nitrate trihydrate. The microstructure of the precursor impregnated with an aqueous solution of copper nitrate trihydrate was confirmed with a scanning electron microscope (SEM), and the particle size and the crystal structure of the copper oxide particles produced as the temperature of the heat treatment of the precursor increased was analyzed by X-ray diffraction (XRD) and the scanning electron microscope (SEM). As a result of the analysis, it was confirmed that the temperature at which the organic matter of the precursor is completely thermally decomposed is 450-490℃, and that the size and crystallinity of the copper oxide particles increased as the heat treatment temperature increased. The size of the copper oxide particles obtained through heat treatment at 500-800℃ during 1 hour was 100nm~2㎛. It was confirmed that the copper oxide crystalline phase is formed at a heat treatment temperature of 400℃, and only the copper oxide single phase existed up to 800℃. And it was also confirmed that the size of particles produced increased as the calcination temperature increased.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.176.1-176.1
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• 2014

Graphene has attracted an increasing attention due to its extraordinary electronic, mechanical, and thermal properties. Especially, the two dimensional (2D) sheet of graphene with an extremely high surface to volume ratio has a great potential in the preparation of multifunctional nanomaterials, as 2D supports to host metal nanoparticles (NPs). Copper oxide is widely used in various areas as antifouling paint, p-type semiconductor, dry cell batteries, and catalysts. Although the copper oxide(II) has been well known for efficient catalyst in C-N cross-coupling reaction, copper oxide(I) has not been highlighted. In this research, CuO and Cu2O nanoparticles (NPs) dispersed on the surface of grapehene oxide (GO) have been synthesized by impregnation method and their morphological and electronic structures have been systemically investigated using TEM, XRD, and XAFS. We demonstrate that both CuO and Cu2O on graphene presents efficient catalytic performance toward C-N cross coupling reaction. The detailed structural difference between CuO and Cu2O NPs and their effect on catalytic performance are discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.10
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• pp.651-655
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• 2017

This work reports the surface morphology and transmittance of copper oxide thin films for semitransparent solar cell applications. We prepared the oxide specimens by subjecting copper thin films to an oxidation reaction at annealing temperatures ranging between $100^{\circ}C$ and $300^{\circ}C$. The color of the as-deposited specimen was red, but changed to purple at the annealing temperature of $300^{\circ}C$. The surface morphology and transmittance of the specimens were significantly dependent on the annealing temperature and thickness of the copper films. Copper oxide nanoparticles prepared from a 20-nm-thick copper film at an annealing temperature of $300^{\circ}C$ provided a maximum transmittance of 93%. The obtained optical characteristics and surface morphology suggest that copper oxide thin films prepared by an oxidation reaction can be potentially employed as color- and transmittance-adjusting layer in semitransparent thin solar cells.

• Korean Journal of Materials Research
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• v.29 no.1
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• pp.37-42
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• 2019

This study investigates Ag coated $Cu_2O$ nanoparticles that are produced with a changing molar ratio of Ag and $Cu_2O$. The results of XRD analysis reveal that each nanoparticle has a diffraction pattern peculiar to Ag and $Cu_2O$ determination, and SEM image analysis confirms that Ag is partially coated on the surface of $Cu_2O$ nanoparticles. The conductive paste with Ag coated $Cu_2O$ nanoparticles approaches the specific resistance of $6.4{\Omega}{\cdot}cm$ for silver paste(SP) as $(Ag)/(Cu_2O)$ the molar ratio increases. The paste(containing 70 % content and average a 100 nm particle size for the silver nanoparticles) for commercial use for mounting with a fine line width of $100{\mu}m$ or less has a surface resistance of 5 to $20{\mu}{\Omega}{\cdot}cm$, while in this research an Ag coated $Cu_2O$ paste has a larger surface resistance, which is disadvantageous. Its performance deteriorates as a material required for application of a fine line width electrode for a touch panel. A touch panel module that utilizes a nano imprinting technique of $10{\mu}m$ or less is expected to be used as an electrode material for electric and electronic parts where large precision(mounting with fine line width) is not required.

• Korean Journal of Materials Research
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• v.32 no.2
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• pp.80-84
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• 2022

Copper nanoparticles (CuNPs) are considered of great importance due to their high catalytic and antimicrobial activities. This study focuses on the preparation and characterization of CuNPs, and on their antibacterial/antifungal activities. A copper salt (copper sulfate pentahydrate) as precursor, starch as stabilizing agent, and ascorbic acid as reducing agent were used to fabricate CuNPs. The resulting product was characterized via different techniques such as X-ray diffractrometry (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) to confirm its characteristic properties. Employing the Scherrer formula, the mean crystallite sizes of copper (Cu) and cuprous oxide (Cu₂O) nanocrystals were found to be 29.21 and 25.33 nm, respectively, as measured from the main X-ray diffraction peaks. The functional groups present in the resulting CuNPs were confirmed by FTIR. In addition, the engineered CuNPs showed antibacterial and antifungal activity against tested pathogenic bacterial and fungal strains.

• Journal of Animal Science and Technology
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• v.66 no.5
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• pp.962-980
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• 2024

Antimicrobial resistance poses challenges to humans and animals, especially to the poultry sector in control of fowl typhoid with antibiotics, leading to increased mortality and food insecurity. Therefore, it is essential to develop more effective medications as alternatives to antibiotics. Currently, zinc oxide and copper oxide nanoparticles are of such significant interest due to their antibacterial properties. This study aimed to evaluate antimicrobial activity of zinc oxide and copper oxide nanoparticles against fowl typhoid in broilers. Ninety broiler chicks were raised under suitable management conditions. On day 10 of age, chicks were divided into six groups: control negative, control positive, T₁, T₂, T₃, and T₄. On day 19 of age, chicks in all groups except control negative were infected with Salmonella gallinarum (0.2 mL, 10⁸ CFU/mL). After appearance of clinical signs, the treatments (Florfenicol; 50 mg/L drinking water [T₁], and zinc oxide + copper oxide nanoparticles; 25 + 10 mg/kg/d [T₂], 37.5 + 15 mg/kg/d [T₃], and 50 + 20 mg/kg/d [T₄]) were administered to chicks. Chicks were sacrificed on 26th and 30th day of age, and samples of blood and tissue were obtained. Hematological analysis with gross and histopathological examination of spleen, thymus and bursa of Fabricius was performed. Results revealed that there was no visible congestion in spleen and thymus of T₃ and T₄ at 11th day post infection. Antibody level against new castle's disease and lymphoproliferative response showed no significant difference in all groups. However, phagocytic response in nanoparticles treated groups exhibited a notable (p < 0.01) distinction compared to control positive. Notably, T₃ demonstrated the highest level of phagocytic activity. Hematological parameters, including lymphocytes, heterophils, eosinophils, and heterophils/lymphocytes ratio in groups T₂, T₃, and T₄, indicated significant (p < 0.01) difference compared to control positive. However, lymphocytes, heterophils, and heterophils/lymphocytes ratio in groups T₂, T₃, and T₄ showed no significant difference when compared to T₁. Nanoparticle treated groups showed decreased (p < 0.01) congestion of spleen and thymus as compared to control positive. Overall, zinc oxide and copper oxide nanoparticles have potential to serve as an alternative to florfenicol in treatment of fowl typhoid.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1561-1564
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• 2008

Although the use of Cu(II) salts as catalysts without reductants is limited in the cycloaddition of acetylenes with azides, the catalytic system employing average 10 nm CuO(II) nanoparticles in the absence of reductants shows good catalytic activity to form 1,4-disubstituted 1,2,3-triazoles even in wet THF as well as water. It is also noticeable that CuO(II) nanoparticle catalysts can be recycled with consistent activity. A range of alkynes and azides were subject to the optimized CuO(II) nanoparticle-catalyzed cycloaddition reaction conditions to afford the desired products in good yields.