CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Shi-Pan Yin,Zhao-Hui Zhang,Xing-Wang Cheng,Tie-Jian Su,Zheng-Yang Hu,Qi Song,Hao Wang
Almost fully dense B 4 C-TiB 2 -SiC composite ceramics with high flexure strength and good fracture toughness were fabricated through in-situ reaction between B 4 C, Ti 3 SiC 2 and Si using spark plasma sintering method at a relatively low temperature of 1650 °C. The intergranular and intragranular structure containing nanoparticles with different phase were introduced into the composite ceramic. The nano and micro particles in the microstructure formed a multi-scale particles reinforced structure. The refined matrix grains and the multi-scale reinforcing particles had a synergetic effect on improving the mechanical properties of the composite ceramics. As a result, B 4 C-TiB 2 -SiC composite ceramic with 30 wt% (TiB 2 + SiC) exhibits low density and optimum mechanical properties with high flexural strength of 531.2 MPa, good fracture toughness of 5.77 MPa m 1/2 and moderate micro-hardness of 28.6 GPa.
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2018
·
IF 2.829
Yuting Meng,Lexin Zhang,Ruirui Xing,Hao Huang,Yuan Qu,Tifeng Jiao,Jingxin Zhou,Qiuming Peng
The fabrication of graphitized diamond covered with polypyrrole (D@G@PPy) core-shell nanocomposites has been achieved by using a superficial electrochemical polymerization and self-assembly strategy. The conductivity of the core-shell nanocomposites was influenced by polymerization time, current as well as the concentration of ions. The obtained excellent conductivity appeared with the current of 0.6 mA and the duration time of 1 h. In addition, the corresponding enhanced electrochemical performance of polypyrrole grown on graphitized diamond substrate is demonstrated compared with pristine polypyrrole. The morphologies of the obtained composites were illuminated through scanning electron microscopy (SEM) and the conductivity was demonstrated by electrochemical impedance spectroscopy (EIS). The characteristic peaks of polypyrrole and qualitative analysis of surface elements have been investigated by Raman spectra and X-ray photoelectron spectroscopy (XPS). The present research could demonstrate a new aspiration for the design and preparation of novel polypyrrole core-shell composites materials.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2018
·
IF 3.046
Xiaoshan Yang,Xiufang Cui,Guo Jin,Jinna Liu,Yanbo Chen,Zhe Liu
Laser additive manufacturing (LAM) is a novel method for processing compositionally graded alloys and becomes increasingly important in the context of next-generation manufacturing technology. In this work, (Fe 60 Co 35 Ni 5 ) 78 Si 6 B 12 Cu 1 Mo 3 soft magnetic alloys with different laser power were designed and processed by the LAM. The magnitudes of magnetic properties were analyzed, and the relationships among composition-microstructure-magnetic properties assessed. Results show that the (Fe 60 Co 35 Ni 5 ) 78 Si 6 B 12 Cu 1 Mo 3 alloys by LAM exhibits relative uniform microstructure and comparable magnetic property compared with those conventional processed alloys. The bcc dominated microstructures exhibit a substantially higher saturation magnetization (Ms). With the increase in power, the average grain size of the alloy increased slightly and the increasing volume fraction of the Fe Si phase leaded to the enhancement of magnetization. The (Fe 60 Co 35 Ni 5 ) 78 Si 6 B 12 Cu 1 Mo 3 alloys with laser power of 3000 W exhibits the highest Ms (199 emu/g). The appearance of Fe 3 B results in coarse dendrites and high coercivity (Hc) in the multiple re-heating cycles.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Qianglong He,Jingjing Xie,Aiyang Wang,Chun Liu,Tian Tian,Lanxin Hu,Chenhong Yi,Zhixiao Zhang,Hao Wang,Weimin Wang,Zhengyi Fu
B x C-TiB 2 -SiC ceramic composites were fabricated via reactive hot pressing using TiC, B, and Si as the raw materials. The phase transition process was studied by heating powder mixtures to different temperatures in combination with X-ray diffraction analysis. The stoichiometric ratio between B and C in boron carbide is variable. A series of powder mixtures containing excess boron (0 wt%, 10 wt%, 20 wt%, or 30 wt% B) were sintered, and the microstructures and mechanical properties of the composites were investigated. The results showed that the B 6.1 C-TiB 2 -SiC composite prepared from the starting powders with 30 wt% excess boron had the best comprehensive mechanical properties , with a relative density, hardness, bending strength , and fracture toughness of 98.32%, 33.2 GPa, 840 MPa, and 5.22 MPa m 1/2 , respectively. Excessive boron substitution may cause lattice distortion in boron carbide , and the boron carbide grains in this state may form a large number of twins under the compressive stress generated by the TiB 2 grains, which will affect the properties of the composites.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 36
·16781-16787
·
IF 6.97
Na Li,Zheng Yi,Ning Lin,Yitai Qian
The application of Si-based anode materials is hindered by their extreme volume change, poor cycling stability, and low coulombic efficiency. Solving these problems generally requires a combination of strategies, such as nanostructure designing or surface coating. However, these strategies increase the difficulty of the fabrication process. Herein, a simple and one-pot replacement reaction route was designed to produce an Al2O3 layer anchored on mesoporous Si nanospheres (Si@Al2O3) by employing Al nanospheres with a naturally formed Al2O3 layer as a reducing agent and self-sacrificial template. The obtained Si@Al2O3 was mesoporous, with enough porous space to buffer the volume change and provide a fast lithium ion transfer channel. Furthermore, the coated Al2O3 layer could stabilize the structure and SEI layer of the mesoporous Si nanospheres, endowing the Si@Al2O3 nanospheres with improved initial coulombic efficiency, cycling performance and rate capability. As a result, a high capacity of 1750.2 mA h g−1 at 0.5 A g−1 after 120 cycles and 1001.7 mA h g−1 at 2 A g−1 after 500 cycles were delivered for lithium ion batteries. The good performance could be attributed to the mesoporous structure and the outer-coated Al2O3 layer.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 29
·期 5
·4179-4189
·
IF 2.019
Han Xiaopeng,Huang Ying,Zhou Suhua,Sun Xu,Peng Xuanyi,Chen Xuefang
Due to the high agglomerate propensity of Si particles, making aluminum composites with a dispersion of the reinforcement using traditional way is still a challenge. In this study, an innovative approach was utilized to prevent the agglomeration of particles using encapsulating graphene sheets by grinding. Afterwards, the milled mixtures were incorporated with Cr-coated graphite flakes, urea and starch via mechanical mixing. After being mechanically mixed and sintered at 330 °C, the porous preform was fabricated by vacuum gas pressure infiltration. Effects of graphene content (0.5, 1, 3, 5 wt%) on the microstructures and properties of thermal and mechanical were investigated. Thermal conductivity and bending strength of the graphite flakes (G f )/Si/Al composites increased by 41.4 and 300%, respectively compared to the specimens without graphene. G f /Si/Al composites with graphene mass fraction of 5% had excellent in-plane thermal conductivity of 346 W/mK and bending strength of 84 Mpa, suggesting the composites can be applied as promising thermal management materials.
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2017
·
IF 13.942
Guodong Zou,Qingrui Zhang,Carlos Fernandez,Gang Huang,Jianyu Huang,Qiuming Peng
Rational design of heterogeneous electrode materials with hierarchical architecture is a potential approach to significantly improve their energy densities. Herein, we report a tailored microwave-assisted synthetic strategy to create heterogeneous hierarchical Ti3SiC2@C-containing Na2Ti7O15 (MAX@C-NTO) composites as potential anode materials for high-performance sodium storage in a wide temperature range from 25 to 80 °C. This composite delivers first reversible capacities of 230 mAh g–1 at 200 mA g–1 and 149 mAh g–1 at 3000 mA g–1 at 25 °C. A high capacity of ∼93 mAh g–1 without any apparent decay even after more than 10 000 cycles is obtained at an ultrahigh current density of 10 000 mA g–1. Moreover, both a high reversible capacity and an ultralong durable stability are achieved below 60 °C for the same composites, wherein a 75.2% capacity retention (∼120 mAh g–1 at 10 000 mA g–1) is achieved after 3000 cycles at 60 °C. To the best of our knowledge, both the sodium storage performances and the temperature tolerances outperform those of all the Ti-based sodium storage materials reported so far. The superior sodium storage performances of the as-synthesized composites are attributed to the heterogeneous core–shell architecture, which not only provides fast kinetics by high pseudocapacitance but also prolongs cycling life by preventing particle agglomeration and facilitates the transportation of electrons and sodium ions by large micro/mesopore structure.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
·
2017
·
IF 9.466
Hongning Chen,Nien-Chu Lai,Yi-Chun Lu
Nonaqueous redox flow battery (RFB) is a promising technology to improve the energy density of RFBs for both stationary grid energy storage and electric vehicle applications. Despite tremendous advancement made in high-capacity flow posolyte, lithium metal has been dominantly exploited as a nonflowable counter electrode in reported lithium-based RFBs to date due to the lack of efficient and high-capacity flow negolyte. Here, we report a silicon–carbon nanocomposite semi-solid negolyte, achieving a high reversible capacity (>1200 mAh g–1) and stable cycle life (>100 cycles). A facile process of incipient wetness impregnation followed by polymerization/carbonization is developed to synthesize monodispersed Si–C nanocomposite with ultrathin graphitic carbon coating. Exploiting Si–C nanocomposite as the negolyte effectively suppresses the volume change of Si particles and enhances the electrical conductivity of the negolyte. Coupling with highly concentrated LiI (5.0 M), we demonstrate the first lithium metal-free Si-based negolyte in a full all-flow cell configuration with a stable cycle life (>60 cycles), high Coulombic efficiency (>90%), and the highest full cell voltage (3.0 V) reported for Li metal-free RFBs. Our successful demonstration of lithium metal-free all-flow battery highlights the promising potential of Si-based negolyte to replace lithium metal for high-energy-density RFBs.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Li Zhao,Li Yang,Yu Cheng,Hong Zhang,Lulu Du,Wei Peng,Ahmed Eissa Abdelmaoula,Lin Xu
Lithium metal is considered as one of the most promising anode material candidates for high-energy-density batteries. However, the solid electrolyte interface (SEI) of the lithium metal surface is susceptible to corrosion by hydrofluoric acid (HF) and H2O, which hinders the practical application of lithium metal. In this work, a functional composite polymer electrolyte (FCPE) containing Si nanoparticles can scavenge HF and H2O to protect the SEI from corrosion. The Si nanoparticles in the FCPE react with HF to form SiF4, which reacts with H2O to produce LiF and LixSiOy without generating other harmful by-products. The LiF and LixSiOy are ionic conductors, which are deposited on the surface of lithium metal constructing an SEI layer with high ionic conductivity. The high ionic conductivity of the SEI can contribute to the induction of uniform Li-ion plating/stripping behavior, thereby preventing the growth of lithium dendrites. As a result, a Li‖Li symmetric cell with the FCPE under extreme conditions with a water content of 8078 ppm (VH2O:Vbase electrolyte = 1.0%) can cycle stably for 800 h. These results highlight that the FCPE can remove water impurities to maintain the excellent performance of lithium metal batteries and provide a direction for the development of polymer electrolytes.
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Jiang Wei,Yan Miao,Wenqian Zhang,Youxin Chen,Guotao Sun,Kaiyu Wu,Qingkang Wang
The development of high Q and tunable narrowband filters that can efficiently manipulate THz beams is critical for various THz applications, such as imaging and sensing. However, for filters made of metals and dielectrics, issues such as high losses, limited tunability, and lengthy process flows exist. Here, a scalable concave version reprinting technique to mass produce high-performance microstructured polymer filters is presented. The technique is extremely simple, eliminating the demand for the use of any large equipment including injection molding and thermal press printing machines, and is reliable; in the reprinted structures, there are no defects including gaps and air bubbles. The produced narrowband filters exhibit a high Q factor of 57 with wide tunability over the THz band from ∼80 to 160 μm in wavelength. The presented technique can be adopted to realize other devices as well using polymer materials with simplicity and high precision.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2012
·
IF 2.237
Xiao Chen,Miao Li,Jingchao Guan,Xinkui Wang,Christopher T. Williams,Changhai Liang
Nickel–silicon intermetallics have been prepared by a direct silicification method using SiH4 as the silicon source. The prepared nickel–silicon intermetallics were characterized by X-ray diffraction, transmission electron microscopy, temperature-programmed reduction, temperature-programmed desorption, X-ray photoelectron spectroscopy, and CO chemisorption measurements. The catalytic hydrogenation of cinnamaldehyde and phenylacetylene over the nickel–silicon intermetallics was investigated. Nickel–silicon intermetallics presented much higher selectivity to the intermediate product (hydrocinnamaldehyde) than monometallic nickel catalyst, which may be attributed to the repulsive force between the electronegative silicon atoms in the nickel–silicon intermetallics and oxygen atoms in the C═O bond of cinnamaldehyde. In addition, nickel–silicon intermetallics showed excellent selectivity for the hydrogenation of phenylacetylene to styrene (ca. 93%) due to the strong modification of the electronic structure derived from the interaction of nickel and silicon.
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2024
·
IF 2.6
Guangrui Han,Lang Liu,Minyu Jia,Xuting Li,Linrui Hou,Changzhou Yuan
Recently, silicon has been considered one of the preferred materials for the anodes of next-generation high-energy-density Li-ion batteries due to its advantages of high specific capacity, low working voltage, and abundant reserves. However, the huge volume change and poor electrical conductivity of silicon anodes during the lithiation and de-lithiation process seriously affect their practical application. Herein, honeycomb porous silicon is synthesized by a modified Stöber method and magnesium thermal reduction, which avoids using toxic gases (such as silane) in the traditional preparation of commercial nano-silicon. Moreover, the honeycomb porous structure can effectively alleviate the volume expansion during the charge/discharge process and agglomeration behavior of nano-silicon. Therefore, thanks to its unique structural merits, the honeycomb porous silicon anode is endowed with a reversible specific capacity of 824.1 mA h g−1 after 100 cycles at 0.5 A g−1 and 679.2 mA h g−1 even at an ultrahigh current density of 1.0 A g−1 after an extended cycling period of 200 cycles, which is almost twice that of commercial nano-silicon. More importantly, this finding offers promising advancements in designing silicon anodes in energy storage.
✓ 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）