TALANTA
·
2021
·
IF 6.057
Pengcheng Ma,Xiaoyan Ma
In this work, based on the dual catalytic properties of copper (Cu) particles for methanol oxidation and persulfate initiated radical polymerization , a temperature-controlled catalytic electrode, defined the PNIPAM-Cu@CP, was constructed by electrodepositing Cu particles on a carbon paper electrode and triggering the polymerization of the temperature-sensitive polymer N-isopropylacrylamide (PNIPAM) on the surface of the electrode, which is expected to be applicated in the micro-direct methanol fuel cell (DMAC) for detection of methanol crossover and also has temperature recognition and high-temperature self-protection functions. Cu particles and PNIPAM were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) for their specific structure and morphology. The cyclic voltammetry (CV) results showed the proposed electrode as a temperature-controlled switch-like methanol sensor, has a wide linear range (1–300 mM and 300–1200 mM), excellent sensitivity (72.8 μA cm −2 mM −1 and 11.5 μA cm −2 mM −1 ) and a low detection limit of 0.3 mM for methanol. In addition, the sensor also has excellent selectivity and temperature-triggered switchable electrocatalytic activity . The efficient and simple preparation method of the electrode is expected to be used in the development of a methanol sensor for real-time methanol detection in micro-DMAC.
研究领域:
材料科学
·
电化学
·
传感技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Mingji Xu,Xi Ran,Ruoli Chen,Maoshen Chen,Ruijuan Qi,Chengqin Dai,Chunhua Luo,Hui Peng,Hechun Lin
Gas sensors based on metal/metal oxide heterostructures have shown rapid advancements due to their excellent sensing performance. However, it is difficult to control the formation of Cu/CuO nanostructure due to the easy oxidation of copper and limits its sensing application. Herein, we reported the controlled oxidation of Cu superfine particles (SPs) to form Cu/CuO nanostructure via reducing CuO with monoethanolamine, oxidized with H 2 O 2 and then in-situ annealed at 250 °C. The organic residue generated during the reducing step plays a key role in controlling the oxidation of Cu SPs to form Cu/CuO nanostructure. The nanomaterial was used to fabricate gas sensor, which presents excellent p-type sensing performance to ethanol with good selectivity and a good linear relationship in the range of 1 to 100 ppm ethanol. The response to 100 ppm ethanol can be up to 99.40 under 200 °C operating temperature, and the response under 250 °C is 30.66 with the shorter response and recovery time of 214 s and 74 s, respectively. The sensing mechanism can be explained by the adsorption–desorption model. This study provides a promising strategy for the synthesis of Cu/CuO nanostructure and open a new avenue for the development of highly sensitive ethanol sensor.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2021
·Vol. 50
·期 6
·3222-3227
·
IF 1.938
Han Wensong,Guo Qin,Su Tianhui
Cu@HBP-SH@Ag particles have been prepared by a facile synthesis strategy. Initially, thiol-terminated hyperbranched polymer (HBP-SH) was synthesized by stepwise polymerization. Subsequently, Cu particles covered with HBP-SH were prepared by reduction technology using HBP-SH as dispersant and template. Finally, Cu@HBP-SH@Ag particles were obtained by reduction reaction. Fourier-transform infrared (FT-IR) and ultraviolet–visible (UV–Vis) spectroscopy confirmed presence of HBP-SH on the surface of the Cu particles. The crystal structure was examined by x-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS) analysis confirmed formation of Cu@HBP-SH@Ag particles. Thermogravimetric analysis (TGA) showed that the Cu@HBP-SH@Ag particles had better antioxidation properties than the Cu particles.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 7
·5954-5960
·
IF 2.324
Wang Yan,Wang Yishu,Han Jing,Tan Shihai,Guo Fu
Sn grain orientation in solder matrix has recently been considered as one of the principal failure contributions in lead-free solder joints. Since β -Sn exhibits high anisotropy, the differences of electromigration behavior of solder joints with various grain orientations are dramatic. With different angle ( θ ) between the c -axis of Sn grain and the direction of electron flow, the solder joints often demonstrate varying degrees of electromigration-induced damage. The present investigation illustrated significant differences in microstructural features on the surface of Cu reinforced composite solder joints, even with similar angle θ . Two Cu particles reinforced Sn 3.5 Ag composite solder joints with the similar angle θ of 35° and 40° were selected to investigate the effects of Sn grain c -axis on electromigration under high current stressing for 528 h. A large number of Cu 6 Sn 5 compounds were observed and occupied nearly the whole surface with clear polarization effect in one sample. In contrast, very few Cu 6 Sn 5 were found on the surface of the solder matrix in the other sample after current stressing, and the Cu 6 Sn 5 which was formed after reflow disappeared with subsequent current stressing. Even though polarization effect was not obvious, and the cathode interfacial dissolution was observed on such sample. Systematic study revealed that the angle θ alone was not a sole factor to determine the electromigration damage. It has to be considered along with the coordinate system containing the orientation of the c -axis of the Sn grain, a more dominative factor for the diffusing species.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xiurong Hou,Huashan Wang,Wei Geng,Lishuang Yang,Jiayue Wang
In this paper, corn starch was modified by acetylation, esterification and amination, and the effects of different modifications on the structure and physicochemical properties of starch were investigated. And starch/copper composite materials were prepared by adding copper salts to the different modified starch, and the influence of modified starch and their additive amount on the morphology of copper and the antimicrobial properties were discussed. The results showed that: the contact angle of the modified starch was about 50° and exhibited hydrophilic-hydrophobic transition; the esterified starch had the smallest heat weight loss; the different modifications caused damage to the structure of the starch, which changed from the original smooth surface to a rough and wrinkled surface; hexahedral morphology copper particles were obtained by replacing them with the modified starch; the antimicrobial effect of the prepared starch/copper composite materials were related to the modification mode of starch, in which aminated starch show the best antimicrobial effect. This study provides a theoretical basis for the selection of starch type in the preparation of starch/copper composite materials in the future, which can also be used as antimicrobial components in other applications.
研究领域:
材料科学
·
生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 28
·285705
·
IF 3.953
Yu Zhang,Qiang Liu,Yu Liu,Jin Tong,Zhongwei Huang,Song Wu,Peilin Liang,Guannan Yang,Chengqiang Cui
A green method for the synthesis of in situ Cu paste is developed. Cu particles are prepared through chemical reduction by selecting a special copper source, reducing agent, and solvent. Then the reaction solution is directly concentrated to obtain an in situ Cu paste. The synthesis of Cu particles and the preparation of Cu paste are conducted simultaneously, and the process of separation, purification, drying, storage, and re-dispersion of powder are reduced. Particles are not directly exposed to air, thus the oxidation of micro/submicron -Cu is effectively prevented, and the agglomeration of particles caused by drying and dispersion operations is simultaneously reduced. Furthermore, the proposed method has a certain universality, and different types of Cu sources can be used to prepare in situ paste with different sizes and morphologies. The entire preparation process is simple, efficient, green, and the yield can reach 99.99%, which breaks through the bottleneck of the application of traditional micro/submicron-Cu materials. Copper acetate-based in situ paste is sintered for 30 min at 260 °C and 2 MPa in a reducing atmosphere. The shear strength, resistivity, and thermal conductivity reach 55.26 MPa, 4.01 × 10–8 Ω·m, and 92.75 W/(m·K), respectively, which could meet the interconnection application of power semiconductor devices.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
WEAR
·
2025
·
IF 6.1
Jinlu Li,Tianyi Sui,Haolin Li,Feifei Zhao,Xuan Bao,Guochen Ning,Yuan Zhang,Jingtao Wang,Bin Lin
Serious wear during running-in period significantly limited the application of ceramics in industry. With poor activity, ceramic contact surface is hard to be protected during friction. In this study, ceramics tribological properties are significantly enhanced and ultra-low friction is achieved in short time by formation of high-strength nano surface film. Copper nanoparticles with linear and cubic morphologies were synthesized and dispersed into water-based lubricants for silicon nitride ceramic friction pairs. A 1:1 mixture of copper nanoparticles with linear and cubic morphologies exhibits the best lubrication performance at an optimal concentration of 0.2 wt%. The result shows an 87.01 % reduction in the coefficient of friction, and a wear rate of 0.18 % of that obtained in the case of deionized water. High-strength protective film is found generated on the ceramic surface, which reduces wear and promotes the forming process of ultra-smooth surface to achieve ultra-low friction. Based on the characterization results, lubrication mechanism is elucidated, quick generation of surface film with high strength is the essential for reducing wear and running-in period.
研究领域:
材料科学
·
摩擦学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 22
·1-11
·
IF 2.8
Liu Sushi,Yang Le,Xin Jianbo,Lv Xiaochun,Chen Yi,Liu Yang
Cu particles sintering is considered one of the most suitable connection technologies for power devices, but Cu has poor oxidation resistance and Cu oxides hinder the sintering process. In this paper, formic acid vapor is used for baking Cu paste to achieve high strength Cu–Cu joints at low temperature. The Cu–Cu joint of 33.9 MPa is obtained easily at 200 °C through baking by formic acid vapor at 130 °C for 15 min. Formic acid vapor effectively reduces the Cu oxides on the surface of the Cu particles, improving the sintering performance of the Cu paste. The effects of baking atmosphere, temperature and time on the shear strength on Cu–Cu joints are analyzed. Additionally, the mechanism of formic acid vapor in reducing the sintering temperature of Cu paste is investigated by the analysis of phase composition and thermal behavior. This work further expands the application of Cu paste in the packaging of high-power semiconductor devices.
研究领域:
材料科学
·
半导体封装技术
✓ 已验证
产品关联
DOI
高影响因子
Energies
·
2022
·Vol. 15
·期 18
·6540
·
IF 3.252
Yan Li,Alberto Maria Gambelli,Federico Rossi
CO2hydrate formation and dissociation are the fundamental processes for investigating hydrate-based carbon storage. To better understand CO2hydrate phase behaviors in the presence of surfactant and solid additives, this study reports the effects of Sodium Dodecyl Sulfate (SDS) and micron Cu particles on the formation of CO2hydrates in the presence of porous quartz sands in a lab-scale reactor. This research is part of a wider study focused on defining the properties of solid additives, produced via gas-atomization, on the formation and dissociation of gas hydrates. The morphology of CO2hydrate formed in SDS solution shows dispersed crystal particles due to the increase of surface tension. SDS works as the kinetic promoter on CO2hydrates formation whereas the addition of Cu particles inhibits CO2gas consumption. The mixture additives show a faint kinetic inhibit effect, in which the Brownian motion restrictions may be responsible for the inhibition of CO2hydrate production. The solid additives also showed a weak thermodynamic effect on CO2hydrate phase equilibrium.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
·
2024
·
IF 6.7
Jianbo Xin,Yue Gao,Chenghao Zhang,Le Yang,Sushi Liu,Ke Li,Minghao Zhou,Yang Liu,Jing Zhang,William Cai
Copper (Cu) particle sintering is widely regarded as one of the most ideal interconnect technologies for wide band gap semiconductors owing to its potential for low-temperature curing while withstanding a higher working temperature. Nevertheless, the strict requirements for sintering conditions and high costs limit the widespread application of Cu sintering technology. In this paper, a simple vehicle was introduced into Cu paste formulation to achieve an effective sinter bonding even using commercially available sub-micron or even micrometer Cu particles (C-Cu particles) with the in-situ generation of composite Cu particles. This innovative vehicle comprises Cu salt, a combination of capping agents and reducing agents. The addition of the hybrid capping agent binds Cu atoms to the surface of the C-Cu particles and allows the generated Cu particles (G-Cu particles) produced from the vehicle to grow on their surface, resulting in the in-situ generation of composite Cu particles. Based on the in-situ generated composite Cu particles, sintering experiments were conducted at designated temperatures (200 °C, 225 °C, 250 °C) for various durations (3 min, 5 min, 10 min) in a N 2 atmosphere under different pressures (10 MPa, 15 MPa, 20 MPa). A reliable Cu sintered joint with a high shear strength of 41.3 MPa can be achieved at a low temperature (200 °C) using 500 nm C-Cu particles. Moreover, the joints sintered with large size (>3 μm) particles at 250 °C could also reach 43.3 MPa. The in-situ generated composite Cu particles accomplish the transformation of low-energy interfaces of C-Cu/C-Cu to high-energy interfaces of G-Cu/G-Cu, which in turn facilitates low-temperature sintered connection of C-Cu particles and reliable sintered joints formed of large size C-Cu particles. These findings improve the feasibility of Cu sinter bonding in practical applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2021
·Vol. 32
·期 50
·505721
·
IF 3.874
Guannan Yang,Haiqi Lai,Wei Lin,Jin Tong,Jun Cao,Jiye Luo,Yu Zhang,Chengqiang Cui
In this paper, the particle size effect on the sintering behaviors of Cu particles at nanometer to micron scale is explored. The results show that micron-sized particles could form obvious sintering necks at a low temperature of 260 °C, exhibiting a shear strength as high as 64 MPa. A power relation of x ∝ a0.8 between sintering neck radius (x) and particle radius (a) is discovered, and a sintering model with a quantitative relational expression of (x/a)5 = 160γδDt/3akT is proposed by considering the surface tension driven microflow process between adjacent particles to predict the growth of sintering necks. It is concluded that the sintering process of particles at nanometer to micron scale is controlled by microflow mechanism instead of diffusion mechanism. Our proposed model provides a new theoretical basis for understanding the kinetic growth mechanism of sintering necks of metal particles.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Yi Wang,Qiming Chen,Chao Liu,Shuo Li,Wei Wu
Cu@TPU composite particles with a structure of TPU core and Cu particles shell were fabricated by in-suite reduction of Cu on the surface of TPU granules. The Cu@TPU composites were then prepared by the hot compression of the as-prepared core-shell particles. The Cu@TPU composite granules were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetric analysis and scanning electron microscopy, which verified that the outer layer of core-shell structure was Cu particles and the connection between Cu and TPU was chemical bonding. The cross-section of Cu@TPU composites showed typical pattern of segregated structure and the surface of those was covered by a layer of Cu particles. With the stacking effect of the special location of Cu and the chemical connection between Cu and TPU, the Cu@TPU composites exhibited a high thermal conductivity of 3.2146 W/m K at 23 vol% filler loading, which was 2.6 times to that of Cu/TPU composites fabricated through simple blending. The TC data of the composites were correlated with Foygel’s model. In addition, the dielectric properties and electrical conductivity of the composites were measured.
研究领域:
材料科学
·
热传导工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）