JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Xiaopeng Han,Ying Huang,Qiao Gao,Rui Fan,Xuanyi Peng
NT@Cu and Ag@GF supported the aluminum (Al) composites had been synthesized by vacuum gas pressure infiltration and their microstructure, Coefficient of thermal expansion (CTE), thermal and mechanical properties were investigated. Cu particles encapsulated with NT had been designed to improve the dispersion of NT and form a carbon conductive network. The chemical plating process was used to enhance the wettability between graphite flakes (GF) and Al matrix and eliminate the harmful interfacial reactions. The composites of NT3 had displayed excellent in-plane thermal conductivity (TC) of 378.48 W/mK and stable CTE in high temperature application environment. What's more, the bending strength had been enhanced to approximately 85.15 Mpa. In this study, the innovative way can be applied to fabricate NT@Cu/Ag@GF/Al composites.
研究领域:
材料科学
·
热力学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Ge Yang,Jinyan Xiong,Mengjie Lu,Weiming Wang,Wei Li,Zhipan Wen,Shaozhong Li,Weijie Li,Rong Chen,Gang Cheng
Photocatalytic CO 2 reduction into valuable fuel and chemical production has been regarded as a prospective strategy for tackling with the issues of the increasing of greenhouse gases and shortage of sustainable energy. A composite photocatalysis system employing a semiconductor enriched with oxygen vacancy and coupled with metallic cocatalyst can facilitate charge separation and transfer electrons . In this work, mesoporous TiO 2 and titanium-based perovskite oxides (BaTiO 3 and SrTiO 3 ) nanoparticle assembly incorporated with abundant oxygen vacancy and copper particles have been successfully synthesized for CO 2 photoreduction . As an example, the TiO 2 decorated with different amounts of Cu particles has an impact on photocatalytic CO 2 reduction into CH 4 and CO. Particularly, the optimal TiO 2 /Cu-0.1 exhibits nearly 13.5 times higher CH 4 yield (22.27 μmol g −1 h −1 ) than that of pristine TiO 2 (1.65 μmol g −1 h −1 ). The as-obtained BaTiO 3 /Cu-0.1 and SrTiO 3 /Cu-0.1 also show enhanced CH 4 yields towards photocatalytic CO 2 reduction compared with pristine ones. Based on the temperature programmed desorption (TPD) and photo/electrochemical measurements, the co-embedding of Cu particles and abundant oxygen vacancy into the titanium-based oxides could promote CO 2 adsorption capacity as well as separation and transfer of photoinduced electron-hole pairs, and finally result in efficient CO 2 photoreduction upon the TiO 2 /Cu, SrTiO 3 /Cu, and BaTiO 3 /Cu composites.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
·
2020
·
IF 3.086
Zhe Ye,Zhenghao Zhu,Ning Ma,Xiaohua Wang,Dingxin Liu,Aijun Yang,Huan Yuan,Mingzhe Rong
The deterioration of transformer oil caused by particle contamination, especially copper particle, seriously affects the safe operation of oil-immersed transformers. Therefore, it is very important for the detection of metal particles in transformer oil. A new method based on laser-induced breakdown spectroscopy (LIBS) was first applied in the transformer oil diagnosis field. By screening out effective spots, the correlation between Cu particle concentration and LIBS signal was obtained after testing a set of oil samples with concentration range from 0.54 to 12.4 μg/g; the calibration curves of Cu I 324.75 nm /CN 358.6 nm and Cu I 327.39 nm /CN 358.6 nm were therefore established. The results shown high linearity, and the determination coefficient R 2 of the two calibration curves in range from 0.54 to 3.1 μg/g were superior to 0.99. The limit of detection (LOD) inferred from Cu I 324.75 nm /CN 358.6 nm fitting curve was 0.77 μg/g and met the critical value specified by industry standards. Due to its flexibility, it can be used as a new-type of particle concentration detection method for transformer oil.
研究领域:
电气工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2017
·Vol. 46
·期 7
·4676-4681
·
IF 1.579
Han Wensong
Third-generation hyperbranched polyester (HBPE3) was synthesized by stepwise polymerization with N , N -diethylol-3-amine methylpropionate as AB 2 monomer and pentaerythritol as core molecule. Then, Cu particles were prepared by reduction of copper nitrate with ascorbic acid in aqueous solution using HBPE3 as template. Finally, Cu/SiO 2 particles were prepared by coating silica on the surface of Cu particles. The structure and morphology of the samples were characterized by Fourier-transform infrared (FT-IR) spectrometry, x-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The results confirmed the formation of the silica coating on the surface of Cu and that the Cu/SiO 2 particles had spherical shape with particle size in the range of 0.8 μ m to 2 μ m. Compared with pure Cu, the synthesized Cu/SiO 2 core–shell particles exhibited better oxidation resistance at high temperature. Moreover, the oxidation resistance of the Cu/SiO 2 particles increased significantly with increasing tetraethyl orthosilicate (TEOS) concentration.
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 24
·20832-20839
·
IF 2.324
Dong Jiannan,Wang Zhongyang,Sun Kai,Jiang Qian,Xie Peitao,Fan Guohua,Qu Yunpeng,An Liqiong,Fan Runhua
Capacitors with a high dielectric constant and low dielectric loss are highly demanded for electronic applications, such as electric devices and energy storage. To enhance the performance of those electronic applications, it is of great significance to achieve capacitors with stable dielectric property both in a broad ranges of frequency and temperature. In this research, flexible Acrylic-polyurethane/copper (APU/Cu) composites with different filler fractions were successfully synthesized. Excellent flexibility of APU/Cu composites is maintained even when Cu particles reached to 19.11 vol%. The dielectric and thermal properties of APU/Cu composites were systematically investigated. Enhanced dielectric constant and lower dielectric loss were achieved. Meanwhile, it is found that the permittivity fluctuated slightly with the increase of frequency and temperature, suggesting that permittivity was independent on frequency and temperature over a broad range. This research shed lights on the application of APU/Cu composites in flexible thin-film capacitors and stretchable electronic devices.
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
Molecular Catalysis
·
2025
·
IF 4.9
Dongmin Zhao,Zhe Hong,Jiantao Liu,Lingling Yin,Hui Bai,Xiaodong Wang,Zhihua Gao,Wei Huang
The valence state and size of copper species play a critical role in the conversion of syngas to higher alcohols. In this study, CuAl binary catalysts with tunable Cu + -Cu 0 ratios and broad size distributions were successfully synthesized by adjusting the heat-treatment pressure of complete liquid-phase method, and their performance in CO hydrogenation was evaluated. The characterization results demonstrated that increasing heat-treatment pressure led to a general increase in both the Cu species size and the Cu⁺/(Cu⁺+Cu 0 ) ratio. Additionally, heat-treated under high pressure significantly enhanced the interaction between the Cu and Al components, promoted the formation of oxygen vacancies on AlOOH, and facilitated electron transfer. Notably, the oxygen vacancy content exhibited a linear correlation with the Cu + /(Cu + +Cu 0 ) ratio. The catalytic performance revealed a synergistic effect between the valence state and size of copper species in promoting higher alcohol synthesis. The percentage of C 2+ OH increased with the rise in Cu + /(Cu + +Cu 0 ) ratio and the size of Cu 0 and Cu 2 O. Among the catalysts, C-4 exhibited the largest Cu 0 and Cu 2 O sizes and the highest Cu⁺/(Cu⁺+Cu 0 ) ratio, achieving the highest proportion of higher alcohols (53.52 %). In-situ DRIFTS experiments also confirmed the synergistic effect of both factors. Larger Cu particles facilitated the dissociative adsorption of CO, while Cu⁺ sites favored the non-dissociative adsorption of CO. This work significantly expands the understanding of the role of Cu + -Cu 0 ratios and larger copper species in syngas conversion, offering valuable insights for the design of Cu-based catalysts with a high selectivity toward C 2+ OH.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Xiaopeng Han,Ying Huang,Qiao Gao,Meng Yu,Xuefang Chen
Weak interfacial bonding and the agglomeration of reinforcements are critical challenges for the expected performance in thermal management materials, hindering the extensive application of aluminum matrix composites. In this work, Cu particles, nanotubes, Ag-coated graphite flakes and films, urea, and starch were mixed together to fabricate porous preforms, which then were infiltrated by vacuum gas pressure at 720 °C. The effects of graphite film thickness on the microstructure and properties of thermal conductivity (TC) and coefficient of thermal expension were investigated. The nanotube@Cu/Ag@graphite/aluminum composites exhibited a high TC of 451 W/mK and excellent bending strength of 74 MPa, which were approximately increased by 48.8% and 126%, respectively, as compared with the samples without graphite film.
研究领域:
材料科学
·
热管理材料
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 2
·2058-2069
·
IF 3.741
Junkai Gao,Xi Tang,Yan Chen,Yi Liu
Summary The thermal conductivity of shape-stabilized phase change material of polyethylene glycols/porous carbon microspheresdoping withcopper particles (PEG/CARM-Cu) was enhanced based on the adsorption and in situ reduction of Cu 2+ using polydopamine microsphere (PDAM)material as the adsorbent. The synthesis of PDAM has the merits of simplicity and environmental friendliness, and the in situ reduction of Cu 2+ through pyrolysis has the advantages of easy operation and cost effectiveness. Copper particles prepared by in situ reduction were tightly fixed on the surface of the support ofporous carbon microsphere (CARM), which avoided the sedimentation of copper particles during the phase change process of PEG/CARM-Cu. According to the SEM, TEM, XRD, TGA and DSC test results, PEG/CARM-Cu possessed favorable thermal reliability and stability, and the phase change enthalpy of PEG/CARM-Cu-2 could reach 101.50 J/g. Additionally, the thermal conductivity of PEG/CARM-Cu-2 (0.497 W/(m·K)) was enhanced by 93.3% compared to that ofpure PEG (0.257 W/(m·K)). Therefore, the PEG/CARM-Cu developed in this paper possessed great potential for real applications.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Yujia Yang,Yujie Tao,Wen Wen,Qiaoru An,Shuang Song,Lejin Xu
Optimization of the synthesis process and promotion of the catalytic efficiency are crucial to develop low-cost and effective catalysts for the removal of antibiotics from wastewater. In our previous work, a kind of hybrid material of nanoscale copper particles anchored on three-dimensional macroporous graphene (3D-GN@Cu) has been proved to be a satisfying Fenton-like catalyst. Herein, the self-assembly methods of 3D-GN@Cu preparation by a facile liquid-phase reduction was further investigated with field emission scanning electron microscopy , nitrogen adsorption/desorption isotherms, Raman spectrum analysis, X-ray diffraction, X-ray photoelectron spectroscopy and cyclic voltammograms measurements. The effects of various reduction methods, reduction time and reducing agent dosage on the physicochemical properties and catalytic performances of 3D-GN@Cu were investigated, and the preparation process was optimized. It was found that 3D-GN@Cu prepared by method A with 1.0 M KBH 4 for 24 h had the largest surface area, the more defects and the best catalytic properties for the removal of metronidazole. In the combination of experimental results and density functional theory (DFT) calculations, the assembly and optimization law for preparing 3D-GN@Cu and the corresponding mechanisms were illustrated. This provides the theoretical basis and new insights for the preparation of graphene-encapsulated nanometals and related composites, which have a promising application potential in the fields of catalysis, electronics, sensors, bioapplications and environmental pollution control.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2020
·
IF 4.794
Li Zheng,Chong Wang,Deng'an Cai,Yunzhong Huang,Kegu Adi,Yan Hong,Yuanming Chen,Guoyun Zhou,Silvia Armini,Stefan De Gendt,Shouxu Wang,Wei He
A novel additive system comprising bis-(sodium sulfopropyl)-disulfide, polyethylene glycol and hydroquinone (HQ) was developed and investigated to achieve high rate copper electrodeposition at high temperature. HQ, as the key additive compound in this system, refines the Cu grain, makes the coating surface bright and smooth at high current density. The underlying mechanism of the additive-assisted electroplating was investigated through electrochemical, morphological characterizations and molecular dynamics simulation. Nanocubical copper particles were found through chronoamperometry tests, which explains the fine crystalline Cu grains and the bright coating surface. Additionally, the formation of the nanocubical copper particles is caused by the different adsorption energies of HQ on (311), (111) and (220) crystal faces and further leads to a strong suppression on the (220) orient crystal faces. Moreover, the electroplating results of through-holes illustrate the feasibility of this additive system in practical applications.
研究领域:
材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Tao Luo,Yanan Yuan,Danna Zhou,Liting Luo,Jinjun Li,Feng Wu
In the recent years, sulfite-induced oxidation of various contaminants using oxysulfur radicals (SO 4 − , SO 5 − and SO 3 − ) has been explored to establish novel advanced oxidation processes (AOPs). Although transition metals, such as cupric ions (Cu(II)), have been demonstrated to be capable of activating sulfite (S(IV)), the catalytic mechanism of the specific Cu(II) species is still not very clear. In this work, N-acetyl- para -aminophenol (APAP) was used as a basic substrate to investigate the process, mechanism and stability of the Cu(II)-S(IV) system with low dosages of Cu(II) (0.010 mmol L −1 ) in an alkaline solution (pH 10). The results show that 0.010 mmol L −1 Cu(II) can efficiently activate S(IV) for the oxidation of APAP and other contaminants (e.g., metoprolol, sulfanilamide, aniline, 4-chloroaniline, N,N-dimethylaniline, p -nitrophenol and 3-nitrophenol). Simulation calculations for the distribution of the Cu(II) species and pH-dependence of APAP oxidation in the Cu(II)-S(IV) system showed that Cu(OH) 2 particles are the major active species in the catalysis of S(IV). The surface complexation of S(IV) with the Cu(OH) 2 particles prior to the production of oxysulfur radicals is the basic mechanism of the alkaline Cu(II)-S(IV) system. Radical inhibition with scavengers (ethanol, tert-butyl alcohol or aniline) demonstrates that SO 5 − , SO 4 − and hydroxyl radicals (HO ) are responsible for the contaminant oxidation. Moreover, SO 5 − is believed to be the main active species in the Cu(II)-S(IV) system, which has a second-order rate constant of 2.98 × 10 8 M −1 s −1 with APAP. This work renews our recognition of the Cu(II)-S(IV) system applications and further understanding of the catalytic role of the nascent Cu(OH) 2 particles in the activation of S(IV).
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Jia Hongyan,Lv Qing,Xia Qineng,Hu Wanpeng,Wang Yanqin
Efficient conversion of biomass-derived 5-hydroxymethylfurfural (HMF) to renewable fuels such as 2,5-dimethylfuran (DMF) and 2,5-dimethyltetrahydrofuran (DMTHF) is of significance for sustainable energy supply. For efficient catalyst design, it is important to understand the catalytic behavior and clarify the influence of physico-chemical properties of catalyst on reaction performance. Herein, to study the structure-activity relationships of monometallic Cu catalysts for HMF hydrogenolysis, a series of Cu/SiO2 catalysts with different physico-chemical properties were prepared and compared for their catalytic performance in HMF hydrogenolysis. It was found that Cu/SiO2-HT-8.5 catalyst prepared by hydrothermal method showed excellent activity in HMF hydrohydrolysis reaction. Under the optimal reaction condition, the total yield of liquid fuels reaches 91.6% with 57.1% yield of DMF and 34.5% yield of DMTHF in THF solvent. Characterizations such as XRD, H2-TPR, N2-adsorption/desorption, TEM and XPS revealed that the Cu particles in the Cu/SiO2-HT-8.5 catalyst have uniform size and high dispersion. The Cu species and the SiO2 support have relatively weak interaction and are easy to be reduced to Cu0, which makes it show excellent activity in the hydrogenolysis of HMF.
研究领域:
催化化学
·
可再生资源与能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）