POLYHEDRON
·
2020
·
IF 2.343
Kaiqian Wang,Shuqiong Zhang,Yalin Cheng,Xinai Yu,Biyang Tu,Haisheng Tao
A novel and effective carbon wrapped manganese oxide material with coaxial-cable structure was synthesized through two processes of hydrothermal method and calcination . Transmission electron microscopy discovered that the as-prepared material had a porous manganese oxide inside core with a diameter of about 100–600 nm and a graphite cable jacket with a thickness of about 20–100 nm. The results of the electrochemical measurements exhibited that the as-prepared material had great energy density , long cycling life and favorable charge-discharge capability when it was used as an anode material in lithium ion batteries . The results revealed that the carbon wrapped manganese oxide was an excellent candidate for the anode of lithium ion batteries.
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高影响因子
IONICS
·
2020
·Vol. 26
·期 7
·3307-3314
·
IF 2.394
Zhu Yuhao,Han Yu,Wang Hui,Guo Qingpeng,Jiang Huize,Sun Weiwei,Xie Wei,Zheng Chunman,Xie Kai
Due to its high capacity and low density, lithium metal is considered as one of the most promising anodes for next-generation lithium batteries. However, the problems of dendrite and volume change are the main obstacles to limit its further development. Therefore, it is of great significance to realize the stable plating and stripping of lithium metal. The stability of lithium metal can be improved by compositing lithium with conductor materials, but the effect of conductor materials on lithium composite anode needs to be further studied. Herein, ionic or electronic conductor powders are introduced into the interior of lithium metal by hot-melt mixed coating method; Li/Cu, Li/Zn, and Li/Li 3 N composite anodes are prepared; and their electrochemical performances in solid and liquid batteries are studied. The results show that plating and stripping of lithium in composite anodes will take place preferentially around electronic or ionic conductor, rather than around lithium itself. For liquid batteries, the introduction of electronic conductor in lithium composite anode will make the electric field distribution more uniform and thus make the lithium deposition more stable, while the introduction of ionic conductor in composite anodes can improve the electrochemical stability of composite anodes in solid-state batteries. The capacity of the Li/Cu-LFP battery was 42.5 mAh g −1 after 500 cycles at 10 °C, corresponding to the 77% retention of its initial capacity.
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高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 27
·9337-9344
·
IF 7.059
Aili Wang,Lili Zhao,Hui Liu,Ziqian Zhou,Chengbo Li,Yong Xiang,Weijia Zhou,Feng Hao
The development of low-dimensional non-precious metal catalysts for the hydrogen evolution reaction (HER) is highly desired for clean energy utilization. Herein, we have reported a facile synthesis protocol of Cu–Mo–O (CMO) nanowires and nanosheets on Cu foam (CMOW/CF and CMOS/CF) through a one-step reaction of Cu nanowires with (NH4)6Mo7O24 solution directly under mild conditions. The final product morphology has been tuned by mechanical stirring. The as-synthesized CMOS/CF exhibits a low operating overpotential of 112 mV at a current density of 10 mA cm−2 with a high electrochemical active area of 25.1 mF cm−2 and excellent long-term stability in the 1 M KOH electrolyte. Moreover, by using the CMOS/CF as cathodic and anodic electocatalysts, a two-electrode electrolyzer capable of driving 10 mA cm−2 at a cell voltage of 1.69 V was achieved, along with promising stability. The high performance of the CMOS/CF can be attributed to higher electrochemical area and more Mo catalytic sites induced by mechanical stirring. This work provides a facile method for the synthesis and catalytic site regulation through a simple method of low-dimensional nanomaterials for the HER with relatively high electrochemical active area and catalytic activity.
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高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 11
·5699-5708
·
IF 11.301
Xin Qian,Dongyang Wang,Yang Zhang,Haijun Wu,Stephen J. Pennycook,Lei Zheng,Pierre F. P. Poudeu,Li-Dong Zhao
The metallic elements with a small atomic radius can not only compensate for the intrinsic vacancies to improve the carrier mobility, but also can form interstitials to reduce lattice thermal conductivity. In this work, we investigate the contrasting roles of three different metallic elements with small atomic radius on the thermoelectric properties of n-type PbM0.01Se (M = Cu, Zn, Ni). We find that all the metallic elements can increase the carrier concentration as electron donors and improve the electrical transport properties. In addition, the lattice thermal conductivity of PbSe can be significantly decreased through the formation of interstitials by the incorporated extra metallic elements. We also find that the PbCu0.01Se sample exhibits a unique and complex behavior compared with the other samples due to the diffusion and the thermally activated oxidation of Cu+ ions. When the temperature increased to 673 K, the carrier concentration of PbCu0.01Se sample increases suddenly and continues to increase by nearly two folds, which we ascribe to the release of 3d orbital electrons in Cu+ ions. This results in a strong decoupling of the charge and heat transport in the material, which can be manifested by the overestimation of the electronic thermal conductivity when assuming strong electron–phonon coupling in Wiedemann–Franz law. A maximum ZT of ∼1.6 can be reached at 773 K and the average ZT of ∼0.96 can be achieved in PbCu0.01Se. Our results demonstrate the exceptional contrasting behavior of Cu in PbSe by comparing with Zn and Ni, and the thermoelectric performance of n-type PbSe can be enhanced through the introduction of extra metallic elements with small radius.
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高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Faqiang Shi,Zhonghua Li,Limeng Liu,Jiandong Wu,Jinfu Ma,Yujin Wang
In previous works, it was found hard to synthesize “phase pure” ζ-Ta 4 C 3-z at relatively low temperatures even by prolonged heating, though ζ-Ta 4 C 3-z was believed stable till decomposition at ~2130°C. When the samples were subjected to TEM , vast richness of locally disordered structures in close relation with stacking of the close-pacted Ta-atom planes was observed. Although kinetic factors including diffusion of C atoms/vacancies and re-stacking of the Ta-atom planes explain the densely disordered structures, the richness of local disorders is a scenario that shows cohabitant of the cubic, rhombohedral, and hexagonal structures in a single grain, i.e. formation of a “hybrid grain” consisted of the three symmetries, indicating a transitional or intermediate stage before complete formation of the final phase of rhombohedral ζ-Ta 4 C 3-z . This time tantalum carbide ceramics TaC x with C:Ta atomic ratios x = 0.66 and 0.7 were prepared by reaction hot pressing of TaC and Ta powder mixtures. 5–30 mol% Cu/Ag additives and heat treatments were used to reproduce “hybrid grains” to facilitate further TEM and HRTEM observations on the disordered hybrid grains to argue for the transitional/intermediate stage. The cohabitant cubic, rhombohedral, and hexagonal structures in single grains may also help explain the difficulty in identification of the various phases by XRD in the transitional/intermediate stage of ζ-Ta 4 C 3-z reaction. Microstructural evolution and fracture toughness of the composites were also investigated.
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高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2021
·Vol. 134
·期 1
·243-257
·
IF 2.081
Zhang Wenfei,Zhou Qulan,Qi Ji,Li Na
Cu 2 O films were prepared using an improved solution immersion method, whereas ZnO/Cu 2 O films were prepared using an electrodeposition method. Then, the pure Cu 2 O film electrodes and ZnO/Cu 2 O film electrodes were used to reduce CO 2 to CH 3 OH. The crystal structure, morphology, particle size, and specific surface area of pure Cu 2 O films prepared under different immersion times and ZnO/Cu 2 O films prepared under different deposition times and Zn 2+ concentrations were analyzed using X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller analysis. The electrolytic activity of the pure Cu 2 O film electrodes and ZnO/Cu 2 O film electrodes were studied. Under the same reaction conditions, the ZnO/Cu 2 O film electrode with the Zn 2+ concentration of 0.05 M and the deposition time of 30 min had the highest total CH 3 OH yield of 315.656 μmol/cm 2 and the fastest formation rate of 52.609 μmol/(cm 2 h), and its faradaic efficiency was 45%, which was remarkably higher than that of pure Cu 2 O film electrodes under the same reaction conditions. This study highlighted that ZnO nanoparticles had a very good promotion of electrolytic CO 2 reduction on Cu 2 O film.
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高影响因子
NANOTECHNOLOGY
·
2021
·Vol. 32
·期 38
·385704
·
IF 3.874
Zhenzhan Yan,Li Yang,Ji-Min Han,HaoJie Li
In the wake of the development of micro-initiation systems, traditional lead-based primary explosives hardly satisfy the needs of high energy output. Copper azide (CA), one of the most promising primary explosives, is restricted in practical applications because of its high electrostatic sensitivity and the method of charge in micro-initiation systems. To tackle these issues, two synthetic paths of CA based on a porous graphene skeleton are proposed. First, a viscous homogeneous mixed solution is rapidly frozen in liquid nitrogen to form a spherical copper-containing precursor material. The copper azide/carbon/graphene composite (CA/C/GA) was fabricated by freeze-drying, high-temperature thermal decomposition and in situ azidation. Second, A cylindrical copper/graphene gel formed by high-temperature hydrothermal self-assembly is served as a precursor material. Also, hydrogen reduction and in situ azidation procedures were utilized to synthesize copper azide@graphene foam (CA@GF). Detailed characterization indicates that the excellent performance of composite materials is ascribed to the excellent electrical and thermal conductivity of graphene material. The electrostatic sensitivities of CA/C/GA and CA@GF were 3.6 mJ and 2.5 mJ, respectively, and the flame sensitivity was 50 cm. The course of fabrication is environmentally friendly and easy to perform and it may be well-matched with the charge of the micro-detonation system.
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PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Xiaoming Wang,Qianqian Peng,Xilin Zhang,Xucheng Lv,Xin Wang,Yongzhu Fu
Refractory high-entropy alloy nanocomposites (HEA-NPs) are important class of materials with unique structure and potential applications. Although several synthetic methods have been reported, developing novel routes to prepare nanoscale HEA-based catalysts facilely is still urgently desired. This work takes advantage of confinement assisted arc and plasma shock (APS) to prepare a series of HEA-NPs by regulating the type and proportion of metal precursors. The phase constitutes and morphology of the HEA-NPs are fully characterized. The prepared refractory HEA-NPs possesses five highly dispersed metal components, including titanium (Ti), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo) and simultaneously exhibits an uniform hexagonal morphology of nanocrystals . By taking advantage of its unique corrosion resistance , TiNbTaCrMo HEA-NPs can function as a promising candidate for electrocatalytic hydrogen evolution reaction (HER) in natural seawater . And its catalytic performance after alloying is significantly enhanced compared with the elemental metal. Theoretically, the promoted HER activity can be attributed to the strong adsorption for the various metal components in HEA-NPs caused by the upshifting d -band center close to the Fermi level . Furthermore, this confinement strategy can be further extended to synthesize other HEA-NPs. Our strategy provides a novel method to synthesize various HEA-NPs for further catalytic application.
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PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 29
·期 7
·9780-9791
·
IF 4.223
Huang Wenqiu,Zhou Yuping,Zhao Ting,Tan Liju,Wang Jiangtao
In this study, the marine microalgae Skeletonema costatum and Nitzschia closterium were exposed to different forms of copper, such as a metal salt (Cu 2+ ), a nano-metal (nano-Cu), and nano-metal oxide (nano-CuO). During a 96-h exposure to nanoparticles (NPs) and salt, the cell number, Cu 2+ concentration in the culture medium, morphology, and intracellular amino acids were measured to assess the toxicity of the copper materials and the toxicity mechanism of the NPs. As results, the toxicity of Cu 2+ , nano-Cu, and nano-CuO to marine phytoplankton decreased in order. The EC 50 values of Cu 2+ and nano-Cu for S. costatum and N. closterium ranged from 0.356 to 0.991 mg/L and 0.663 to 2.455 mg/L, respectively. Nano-Cu inhibits the growth of marine phytoplankton by releasing Cu 2+ ; however, nano-CuO is harmful to microalgae because of the effect of NPs. The secretion of extracellular polymeric substances by microalgae could also affect the toxicity of nano-Cu and nano-CuO to microalgae. S. costatum was more sensitive to copper than N. closterium . Cu 2+ , nano-Cu, and nano-CuO all reduced per-cell amino acids and the total output of algae-derived amino acids by affecting the growth of the phytoplankton. This study helps to understand the risk assessment of nano-Cu and nano-CuO to marine microalgae.
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PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Yulei Yuan,Houya Wu,Junjie Li,Pengli Zhu,Rong Sun
The development of WBG (wide bandgap) semiconductors has put forward higher requirements for packaging and interconnection technology. Cu sintering is widely considered as an advanced interconnection technology which can be used in high temperature and high power density service. In this paper, a new type of self-reducible Cu nanoparticle paste was proposed to solve the problems of easy oxidation and high sintering temperature of normal Cu nanoparticles. The proposed Cu paste was developed by mixing formic acid treated Cu nanoparticles, reducing solvents and MOD (metal organic decomposition) solutions. Based on the new type of self-reducible Cu nanoparticle paste, Cu-Cu bonding experiments were carried out with different bonding temperature and time, and a reliable Cu-Cu joint with a high shear strength of 52.01 MPa can be achieved at 250 °C under ambient condition, without any assistance of reducing or inert atmosphere. In addition, the MOD assisted self-reduction and sintering mechanism was proposed after shear strength testing, element composition analyzing, cross-sectional morphology and fracture structure observation, which can provide an effective theoretical support for the practical application of Cu-Cu bonding.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Xin Liu,Peng Xu,Qi Fu,Runhan Li,Chenxi He,Wenxuan Yao,Lei Wang,Shiqi Xie,Zhiyi Xie,Qiulai He,John C. Crittenden
Zero − valent copper activated peroxymonosulfate (Cu(0)/PMS) system had widely studied for degrading contaminant due to being highly efficient. However, the weak reactivity and easy dismutation of Cu(I) in acid condition restrained its efficiency. In our study, ferric ion (Fe(III)) significantly enhanced Cu(0)/PMS system for acetaminophen degradation and total organic carbon removal. Multiple reactive oxidants including Fe(IV), Cu(III) and hydroxyl radical (•OH) were generated in the Fe(III)/Cu(0)/PMS system. In the Fe(III)/Cu(0)/PMS system, Cu(0) generated Cu(I) by hydrogen corrosion and PMS oxidation, and then Fe(III) reacted with Cu(I) and Cu(0) producing Fe(II). At the same time, PMS reduced Cu(II) to Cu(I), and Cu(I) reacted with oxygen with forming hydrogen peroxide (H 2 O 2 ). Finally, both Cu(I) and Fe(II) induced H 2 O 2 and PMS producing reactive oxidants, and meanwhile H 2 O 2 was formed by the reaction of Fe(IV) and •OH. Thereinto, Fe(IV) and •OH made main contribution on the degradation of acetaminophen, while Fe(IV), Cu(III) and •OH were responsible for orange II degradation. Common water matrix including sulfate ion, nitrate ion and carbonate ion had inapparent impact on acetaminophen degradation, but chloride ion and humic acid limited slightly the degradation of acetaminophen. There had a good degradation of acetaminophen in tap water, lake water and well water with the Fe(III)/Cu(0)/PMS system. Adjusting the final reaction solution to pH 8.0 and subsiding, the discharge of total copper was within the II-level environmental quality standards for surface water in China (1 mg/L). The study might provide a new and promising idea based on Cu(0) activated PMS system for enhanced degradation of contaminants.
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高影响因子
RARE METALS
·
2021
·Vol. 41
·期 3
·931-941
·
IF 4.003
Guo Jun,Wang Zi-Yuan,Zhu Yu-Ke,Chen Lin,Feng Jing,Ge Zhen-Hua
Bi 2 S 3 is composed of inexpensive and environmental friendliness elements, which has received extensive interests and been investigated as a promising mid-temperature thermoelectric material for years. Even pure Bi 2 S 3 possesses a high Seebeck coefficient and low thermal conductivity, its low electrical conductivity leads to a low figure of merit (ZT) value. In this work, Bi 2 S 3 fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl 3 . Cu interstitial doping and Cl substitution on S site result in a large increase in electrical conductivity. Additionally, the enhanced phonon scattering is derived from the point defects caused by element doping, the grain boundaries, and the small amount of secondary phase, which leads to the low thermal conductivity. Finally, a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature (RT) to 773 K for the Cu-interstitial-doped and BiCl 3 -alloyed (Cu 0.01 Bi 2 S 3 + 0.175 mol% BiCl 3 ) sample. Furthermore, the mechanical properties of the Cu 0.01 Bi 2 S 3 + 0.175 mol% BiCl 3 sample are lower than those of other Bi 2 S 3 samples, which stem from the weak chemical bonding strength. Graphic abstract
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高影响因子
危险品化学品经营许可证（带存储）