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Preparation of cu nanoparticles with NaBH_4 by aqueous reduction method

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Transactions of Nonferrous Metals Society of China 2012年第1期22卷 117-123页

作者： LIU Qing-ming ZHOU De-bi Yuya YAMAMOTO Ryoichi ICHINO Masazumi OKIDO School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Department of Materials Science Graduate School of EngineeringNagoya UniversityNagoya 4648603Japan

cu nanoparticles were prepared by reducing cu2＋ ions with NaBH4 in alkaline solution. The effects of NaBH4 concentration and dripping rate on the formation of cu nanoparticles were studied. The optimum conditions are found to be 0.2 mol/L cu2＋, solution with pH=12, temperature of 313 K and 1% gelatin as dispersant, to which 0.4 mol/L NaBH4 is added at a dripping rate of 50 mL/min. NH3-H2O is found to be the optimal complexant to form the cu precursor. A series experiments were conducted to study the reaction process at different time points.

关键词： cu nanoparticles aqueous reduction method precursor reaction process

Preparation of cu nanoparticles with ascorbic acid by aqueous solution reduction method

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Transactions of Nonferrous Metals Society of China 2012年第9期22卷 2198-2203页

作者：刘清明 Takehiro YASUNAMI Kensuke KURUDA Masazumi OKIDO 名古屋大学工学部材料科学系日本4648603 中南大学化学化工学院长沙410083

cu nanoparticles were prepared by reducing cu2＋ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of cu2O particles on the preparation of cu nanoparticles were investigated. cu particles were prepared at pH 3, 5 or 7, with the smallest cu particles obtained at pH 7. However, cu particles could not be prepared at pH 9 or 11. The average size of cu2O particles can affect that of cu particles. Larger cu2O particles result in larger cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction （XRD） patterns of specimens collected at different time points during the reaction. It was found that cu（OH）2 was initially formed as a precursor, followed by the formation of cu2O, which was finally reduced to cu particles.

关键词： cu nanoparticles aqueous solution reduction method ascorbic acid intermediate product

Synthesis of cu nanoparticles by chemical reduction method

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Transactions of Nonferrous Metals Society of China 2019年第7期29卷 1510-1515页

作者： M. S. AGUILAR R. ESPARZA G. ROSAS Instituto de Investigación en Metalurgia y Materiales UMSNH Morelia Michoacán 58000 Mexico Centro de Física Aplicada y Tecnología Avanzada UNAM Santiago de Querétaro 76230 Mexico

cu nanoparticles (cuNPs) have been synthesized through an easy route by chemical reduction at room temperature. The cu^2+ ions were reduced and stabilized with sodium borohydride and polyvinylpyrrolidone, respectively. The effect of the variation of the reducing agent/precursor-salt (RA/PS) ratio on the size and morphology of the cuNPs was evaluated. The synthesized material was studied by ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The UV-Vis spectra showed a cuNPs plasmon peak at 569 nm and another peak belonging to cu2O at 485 nm. XRD analysis showed the fcc-cu phase with a small amount of fcc-cu2O compound. SEM and TEM studies displayed that small semispherical cuNPs of approximately 7 nm were obtained at the RA/PS ratio of 2.6. The excess of polyvinylpyrrolidone stabilizer played an essential role in preventing cuNPs oxidation. On the other side, cu2O polyhedral particles with larger sizes up to 150 nm were identified in the RA/PS ratio range of 2.0-1.84. In addition, cu2O particles having star morphologies with quantum confinement at their tips were obtained at the RA/PS ratio of 1.66.

关键词： cu nanoparticles NaBH4 chemical reduction polyvinylpyrrolidone stabilization cu2O

Effects of reaction parameters on preparation of cu nanoparticles via aqueous solution reduction method with NaBH_4

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Transactions of Nonferrous Metals Society of China 2012年第12期22卷 2991-2996页

作者：刘清明周德璧 Yu-ya YAMAMOTO Kensuke KURUDA Masazumi OKIDO 中南大学化学化工学院长沙410083 Department of Materials Science Graduate School of Engineering Nagoya University

The preparation of cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of cu nanoparticles were studied. The optimum conditions for preparing well-dispersed nanoparticles were found as follows: 0.4 mol/L NaBH4 was added into solution containing 0.2 mol/L cu2+, 1.0% gelatin dispersant in mass fraction, and 1.2 mol/L NH3?H2O at pH 12 and 313 K. In addition, a series of experiments were performed to discover the reaction process. NH3?H2O was found to be able to modulate the reaction process. At pH=10, cu2+ was transformed to cu(NH3)42+ as precursor after the addition of NH3?H2O, and then cu(NH3)42+ was reduced by NaBH4 solution. At pH=12, cu2+ was transformed to cu(OH)2 as precursor after the addition of NH3?H2O, and cu(OH)2 was then reduced by NaBH4 solution.

关键词： cu nanoparticles NaBH4 cu(OH)2 cu(NH3)42+ aqueous solution reduction method precursor reaction process

Enhancement of Polar Kerr Effect by Forming cu nanoparticles on Ni Surface

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Enhancement of Polar Kerr Effect by Forming Cu Nanoparticles...

Enhancement of Polar Kerr Effect by Forming cu nanoparticles on Ni Surface

中国颗粒学会2004年年会暨海峡两岸颗粒技术研讨会会议

作者：任盛源江海邦陈冠章 Institute of Physics Academia SinicaTaipei 11529China Institute of Optoelectronic Sciences NTOUKeelung 202China Institute of Physics Academia SinicaTaipei 11529China

＜正＞cu（x）/Ni（y）/glass bi-layer films, with x ranging from 10 to 310 A and y = 85 A, were made by the vapor evaporation method in a good vacuum. The surface morphology of each bi-layer was examined by an atomic force microscope （AFM）. The results show that when x = 10 and 40 A, respectively, there are, in particular, a large number of cu nanoparticles （or nano-islands） forming on top of the Ni surface. As a result, we observed considerable enhancement of either the polar Kerr rotation （θK） or theextraordinary Hall coefficient （RS） at these two thicknesses （e.g. checking the figure below）. As well known, the penetration depth （δp） of the polarized electrons, crossing the cu/Ni interface from the Ni to the cu layer. is of the order of the electron mean free path, i.e. δp =（3/8）[cu≈90 A. in the cu layer. Therefore. the strong enhancement of θK is due to the enhanced surface plasma resonance effect on the polarized cu nanoparticles. Moreover, the formation of cu nanoparticles roughens the bi-layer’s surface greatly. That means the enhancement of Rs is due to the increase of the surface resistivity ρs.

关键词： cu nanoparticles magneto-optical Kerr effect Hall effect

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过程工程学报 2004年第Z1期4卷 32-32页

作者：任盛源江海邦陈冠章 Institute of Physics Academia Sinica Taipei 11529 China Institute of Optoelectronic Sciences NTOU Keelung 202 China

cu(x)/Ni(y)/glass bi-layer films, with x ranging from 10 to 310 A andy = 85 A, were made by the vapor evaporation method in a good vacuum. The surface morphology of each bi-layer was examined by an atomic force microscope (AFM). The results show that when x = 10 and 40 A, respectively, there are, in particular, a large number of cu nanoparticles (or nano-islands) forming on top of the Ni *** a result, we observed considerable enhancement of either the polar Kerr rotation (θk) or the extraordinary Hall coefficient (Rs) at these two thicknesses (e.g. checking the figure below). As well known, the penetration depth (δp), of the polarized electrons, crossing the cu/Ni interface from the Ni to the cu layer, is of the order of the electron mean free path, i.e. δp =(3/8)[cu≈90 A. in the cu layer. *** strong enhancement of θK is due to the enhanced surface plasma resonance effect on the polarized cu nanoparticles. Moreover. the formation of cu nanoparticles roughens the bi-layer's surface *** means the enhancement of Rs is due to the increase of the surface resistivity ρs.

关键词： cu nanoparticles magneto-optical Kerr effect Hall effect

Photothermal properties of cu@polycarbonate composites with strong localized surface plasmon resonances

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Nano Research 2024年第9期17卷 8513-8520页

作者： Fengyi Wang Jiangling He Junshan Hu Zhihui Chen Yumeng Shi Qing-Hua Xu SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of EducationInstitute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Copper is relatively low cost and highly abundant compared with the well-studied noble metals such as gold and ***,the poor plasmonic and high susceptibility towards oxidation limit the study of its optical properties and applications as ***,copper nanoparticles@polycarbonate(cu@PC)composites were prepared by using a facile one-step solvothermal *** cu@PC composites have strong localized surface plasmon resonances(LSPR)due to that the PC shell can induce the particles to form many-particles system with different particle numbers,which not only lead to overlap and hybridize of the LSPR modes,but also shift the LSPR away from the interband transitions,and the PC layer also prevents the oxidation of cu *** photothermal conversion efficiency of cu@PC composites reaches 41.1%under 808 nm continuous wave(CW)laser irradiation which is higher than previously reported cu nanomaterials that have been ***,the composites also have high photothermal ***,interfacial evaporator is prepared by assembling the cu@PC composites on scouring sponge as light absorption layer which has>92.8%absorption in entire solar spectrum *** seawater evaporation rate is 3.177 kg·m^(-2)·h^(-1)with a E_(evaporator)/E_(water)of *** high evaporation rate interfacial evaporator with low cost,simple,and scalable approach shows great application value in the field of photothermal evaporation.

关键词： cu nanoparticles localized surface plasmon resonances(LSPR) photothermal interfacial evaporation

Exploring the impact of Nafion modifier on electrocatalytic CO_(2) reduction over cu catalyst

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Journal of Energy Chemistry 2024年第1期88卷 543-551,I0012页

作者： Yingshi Su Yonghui Cheng Zhen Li Yanjia cui Caili Yang Ziyi Zhong Yibing Song Gongwei Wang Lin Zhuang College of Chemistry&Chemical Engineering and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou 515063GuangdongChina College of Chemistry and Molecular Sciences Hubei Key Lab of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina The Institute for Advanced Studies Wuhan UniversityWuhan 430072HubeiChina Department of Chemistry Engineering Guangdong Technion-Israel Institute of Technology(GTIIT)Shantou 515063GuangdongChina Technion-Israel Institute of Technology(IIT) Haifa 32000Israel

Nafion as a universal polymer ionomer was widely applied for nanocatalysts electrode ***,the effect of Nafion on electrocatalytic performance was often overlooked,especially for CO_(2)***,the key roles of Nafion for CO_(2)RR were systematically studied on cu nanoparticles(NPs)*** found that Nafion modifier not only inhibit hydrogen evolution reaction(HER)by decreasing the accessibility of H_(2)O from electrolyte to cu NPs,and increase the CO_(2)concentration at electrocatalyst interface for enhancing the CO_(2)mass transfer process,but also activate CO_(2)molecule by Lewis acid-base interaction between Nafion and CO_(2)to accelerate the formation of^(*)CO,which favor of C–C coupling for boosting C_(2)product *** to these features,the HER selectivity was suppressed from 40.6%to 16.8%on optimal cu@Nafion electrode at-1.2 V versus reversible hydrogen electrode(RHE),and as high as 73.5%faradaic efficiencies(FEs)of C_(2)products were achieved at the same applied potential,which was 2.6 times higher than that on bare cu electrode(~28.3%).In addition,Nafion also contributed to the long-term stability by hinder cu NPs morphology ***,this work provides insights into the impact of Nafion on electrocatalytic CO_(2)RR performance.

关键词： Nafion modifier CO_(2)reduction cu nanoparticles In situ ATR-SEIRAS C_(2)product

Recent progress on copper catalysts with different surface states for CO_(2)electroreduction

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Journal of Energy Chemistry 2024年第1期88卷 10-27,I0001页

作者： Wenjun Zhang Yang Yang Donggang Guo Lu Liu Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Shanxi Laboratory for Yellow River College of Environment and ResourceShanxi UniversityTaiyuan 030006ShanxiChina

The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy ***,only copper(cu)can currently achieve stable and efficient hydrocarbon conversion in the eCO_(2)***,understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of cu catalysts are essential for the eCO_(2)*** paper reviews cu catalysts with different surface states of cu catalysts:oxide-derived cu,cu nanoparticles,cu single atoms,and cu *** then reviews the development and progress of different cu-catalyst preparation methods in recent years,focusing on the activity and selectivity of *** revealing the tendencies of catalytic selection and deep reactive mechanisms of cu catalysts with four different surface states,this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms.

关键词： eCO_(2)RR Oxide-derived cu cu nanoparticles cu single atoms cu nanoclusters