• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.141-141
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• 2018

Copper is one of the most abundant metals on earth. Its oxide (CuO) is an intrinsically p-type metal-oxide semiconductor with a bandgap ($E_g$) of 1.2-2.0 eV 1. Copper oxide nanomaterials are considered as promising materials for a wide range of applications e.g., lithium ion batteries, dye-sensitized solar cells, photocatalytic hydrogen production, photodetectors, and biogas sensors 2-7. Recently, high-density and uniform CuO nanostructures have been grown on Cu foils in alkaline solutions 3. In 2011, T. Soejima et al. proposed a facile process for the oxidation synthesis of CuO nanobelt arrays using $NH_3-H_2O_2$ aqueous solution 8. In 2017, G. Kaur et al. synthesized CuO nanostructures by treating Cu foils in $NH_4OH$ at room temperature for different treatment times 9. The surface treatment of Cu in alkaline aqueous solutions is a potential method for the mass fabrication of CuO nanostructures with high uniformity and density. It is interesting to compare the gas sensing properties among CuO nanomaterials synthesized by this approach and by others. Nevertheless, none of above studies investigated the gas sensing properties of as-synthesized CuO nanomaterials. In this study, CuO nanowalls versus nanoparticles were synthesized via the oxidation process of Cu foil in NH4OH solution at $50-70^{\circ}C$. The gas sensing properties of the as-prepared CuO nanoplates were examined with $C_2H_5OH$, $CH_3COCH_3$, and $NH_3$ at $200-360^{\circ}C$.

• Advances in nano research
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• v.16 no.5
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• pp.501-508
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• 2024

In this study, nanotoxicity tests were made by exposure of Artemia salina to copper (Cu 60-80 nm) and copper oxide (CuO 40 nm) nanoparticles (NPs) at different concentrations (0.2, 1, 5, 10, 25, and 50 mg/L). The LC₅₀ value of Cu (60-80 nm) NPs on the A. salina individuals at the beginning (0), 24^th, 48^th and 72^nd hours and elimination period was 52.37 mg/L while the LC₅₀ value of CuO (40 nm) NPs was 55.39 mg/L. The results of UV-Vis absorbance values showed that all statistical data revealed that maximum effect was observed between 24-30 hours and 25 ppm absorbance concentration was more effective. The multiple R, correlation coefficient (R2) and adjusted R2 values of Cu NP for the suitable Quadratic model were, respectively; 92.96 %, 86.42 % and 76.71 % while they are 98.31 %, 96.64 % and 94.25 % for CuO NP. Also, the data, was indicated effect size significantly changed based on the type and size of NP. Considering the microscope results, it was clearly noticed that A. salina organisms took the NPs in to their body. The accumulation in the gut of A. salina was observed and the images were taken with phase contrast microscope for both of NPs. The highest decrease for survival rates of A. salina individuals exposed to Cu NP was observed in the 10 ppm concentration (43.47 %) and in the 5 ppm concentration (46.20 %) for CuO NP. The results revealed that Cu and CuO NPS showed different toxic effects and that Cu NPs were more toxic than CuO.

• Journal of Powder Materials
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• v.12 no.6 s.53
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• pp.441-446
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• 2005

The copper oxide nano powders were synthesized by levitational gas condensation (LGC) method, and were applied to catalyst to fabricate 3,4-dihydropyrimidin-2-(1H)-one. Processes of adsorption of Biginelli reaction reagents on the copper nanooxide surface $Cu_2O{\circ}CuO$ were studied by IR-spectroscopy. It was shown that benzaldehyde coordination, acetoacetic ether on the oxide surface is carried out with participation of carbonyl fragments, urea by N-H bonds which affects positively on the reagents reactivity.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.453-453
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• 2013

유기 태양전지는 저비용으로 제작이 가능하고 제작이 용이한 장점을 가지고 있으므로 많은 그룹에서 관심을 가지고 있다. 정공 수송층으로 사용되는 PEDOT:PSS는 많이 사용되지만 강한 산성 특성 때문에 ITO 전극에 식각이 되므로 문제가 있다. 그러므로 산화물 반도체 $WO_3$, $MoO_3$, 그리고 $V_2O_3$ 등이 태양전지에 많이 만들어지고 있다. 특히 copper oxide는 높은 광흡수율을 가지고 있으므로 태양전지에 사용하는 데 많은 기대되는 물질이다. Copper oxide 박막은 열증착 법, 스프레이 필로시스, 전기화학 증착, 화학증착법, 그리고 솔-젤법 등 다양한 증착 방법이 있다. 넓은 면적의 소자를 제작할 경우 솔-젤 방법은 기존의 증착법에 비해 낮은 비용으로 제작, 높은 성장율, 그리고 높은 기계적 탄력성의 장점이 있다. 솔-젤법으로 만든 copper oxide는 P3HT의 HOMO (high occupied molecular orbital)와 비슷한 위치에 접하고 있으므로 정공수송층으로 적합하다. 본 연구에서 제작된 태양전지의 구조는 ITO/P3HT:PCBM/CuxO로 구성되어 있다. ITO가 $10{\Omega}$/sq의비저항을 가지고 있었고 UV 처리를 하였다. 그 위에 P3HT:PCBM (1:0.8 weight)를 스핀 코팅하였다. 마지막으로 0.1 M $Cu_xO$용액은 Cu (II) acetate monohydrate를 소스로 2-methoxyethanol ($C_3H_8O_2$)의 용제와 안정제로 monoethanolamine ($C_2H_7NO$)을 섞어서 만들었다. 그리고 P3HT:PCBM 위에 스핀 코팅하였고 열증착 방법으로 전극인 Ag 을 증착하여 최종 소자를 만들었다. Cu(II) acetate의 소스로 제작된 박막의 투과율 측정을 통해 에너지 밴드갭을 구할 수 있었다. Copper oxide 박막은 다결정구조 이므로 다중 밴드갭으로 구성되어지는 것을 알 수 있었다. 최종적으로 만들어진 소자를 열처리를 통해 소자 특성을 조사했더니 250도에서 가장 좋은 결과를 얻을 수 있었다.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.491-498
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• 2014

In order to obtain basic data for concentration control of alkaline copper quat (ACQ) solution in wood preservative treatment, this study investigates the change of concentration and adsorption of treating solution and active ingredient, copper oxide (CuO) and didecyldimethyl ammonium chloride (DDAC), in the process of recycling of ACQ solution. Japanese larch (Larix leptolepis), Douglas-fir (Psedotsuga menziesii) and Radiata pine (Pinus radiata) were treated with ACQ solution. The active ingredient concentration of ACQ solution was decreased continuously with increase of recycling. There are differences between extent of concentration decrease of Cu (as CuO) and DDAC. DDAC was decreased more quickly and to a higher degree than Cu for all recycling. The extent of DDAC concentration decrease was remarkable than that of Cu for wood species. The amount of DDAC adsorbed into wood decreased with the increase of ACQ solution recycling, but adsorption of Cu was little difference regardless of recycling. The adsorption of Cu into wood increased as DDAC concentration decrease by recycling of ACQ solution. This is likely due to decrease of DDAC competition with Cu for the same reaction site in wood.

• Journal of the Korean institute of surface engineering
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• v.5 no.3
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• pp.77-85
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• 1972

A method of preparation of synthetic ignorgaic coating on copper (patina) has been presented . An Eh--pH diagram was constructed for the present Cu-H2O-SO$_4$ system using the most recently available thermodynamic data. In the path of the patination at room temperature the general behaviour of copper in acidic copper sulfate solutions with potassium chlorate as an oxidizing agent appeared to follow those predictable in this Eh-pH diagram. In the presence 0.05 molar cupric sulfate at a temperature of about 28$^{\circ}C$ a green brochantite (CuSO$_4$$.$3Cu(OH)$_2$) layer was formed on copper sheet in 20 days. In a solution having an initial pH of 3.5 the development of a brochantite coating has been observed to take place in two stages. In the first, a layer of cuprous oxide formed on the copper at a relatively rapid rate. In the ensuing step the outer layer of cuptrite was oxidized at much slower rate to form brochantite. The syntetic coatings appeared to consist of crystal-lites of brochanitite growing perpendicular to the cuprose oxide surface. The outer tips of the -crystallites were reasily broken off and gave to the layer a rather chalky character. Underneath, at the brochantite Cu$_2$O interface, however, the green layers were firmely attached. The effect of reagent concentration , solution agitation , and moderate temperature increase were investigated to improve the quality of coating. So also in a qualitative way were the effect of light.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.842-844
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• 2004

Ternary tellurite glassy systems $(CuO-V_2O_5-TeO_2)$ have been synthesised using tellurium oxide as a network former and copper oxide as network modifier. The addition of a transition-matal oxide makes them electric or mixed electric-ionic conductors, which are of potential interest as cathode materials for solid-state batteries. This glass-ceramics crystallized from the $CuO-V_2O_5-TeO_2$ system are particularly interesting, because they exhibit high conductivity ( up to $6.03{\times}10^{-3}S/cm$) at room temperature. the glass samples were prepared by quenching the melt on the copper plate and the glass-ceramics were heat-treated at crystallizing temperature determined from differential thermal analysis (DTA). The electric D.C conductivity result have been analyzed in terms of a small polaron-hopping model.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.193-199
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• 2006

The catalytic oxidation of toluene over $-Al_2O_3$ supported copper-manganese oxide catalysts in the temperature range of $160-280^{\circ}C$ was investigated by employing a fixed bed flow reactor. The catalysts were characterized by BET, scanning electron microscopy (SEM), temperature-programmed reduction(TPR), temperature-programmed oxidation(TPO), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction(XRD) techniques. Catalytic oxidation of toluene was achieved at the below $280^{\circ}C$, and the optimal content of copper and manganese in the catalyst was found to be 15.0 wt％Cu-10.0 wt％Mn. From the TPR/TPO and XPS results, the redox peak of 15 Cu-10 Mn catalyst shifted to the lower temperature, and the binding energy was shifted to the higher binding energy. Furthermore, It is considered that $Cu_{1.5}Mn_{1.5}O_4$ is superior to Mn oxides and CuO in the role as active factor of catalysts from the XRD results and also catalytic activities are dependent on the redox ability and high oxidation state of catalysts.

• 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.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.124-129
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• 2005

Copper oxide, CuO, are very important components include of high temperature super- conductors, and widely used. The properties of sintered materials were affected by the size and shape of copper oxide with starting materials in the solid-phase reaction. A homogeneous and fine CuO powder was prepared by thermal decomposition of the copper oxalate precursor. Copper oxalate was precipitated by the addition of copper nitrate solution to an oxalic acid solution. The influence of various factors such as temperature, pH, concentration as well as ultrasonic irradiation in the solution were investigated.