JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Nan Liu,Zhi Dong,Zongqing Ma,Liming Yu,Chong Li,Chenxi Liu,Qianying Guo,Yongchang Liu
The bimodal distribution of tungsten grain size, which is also called bimodal structure, is a universal phenomenon in synthesizing tungsten based nanopowders by wet chemical method , and could significantly deteriorate further sintering characteristics of the powders. In this paper, W-Y 2 O 3 composite nanopowders with small grain size and no bimodal structure were synthesized by an improved wet chemical method. It was found that reaction conditions, especially the hydrogen ion concentration(ρ(H + )) could significantly influence the microstructure and morphology of the prepared composite nanopowders and has an optimum value of approximately 0.16 mol L −1 . W-Y 2 O 3 composite nanopowders synthesized under this optimum value got not only the minimum average grain size, which is about 17 nm, but also the best grain size uniformity with no bimodal structure. The microstructure of co-deposited precursors and prepared powders was analyzed in detail to figure out the specific influence mechanism of ρ(H + ), and it was indicated that ρ(H + ) could influence the microstructure and the Y 2 O 3 content of the reduced powders through affecting the fraction of precursor that has little yttrium content, which may lead to the bimodal distribution of tungsten grain size of the prepared powders. Furthermore, the formation mechanism of bimodal structure was systematically analyzed and a feasible method was proposed to eliminate the bimodal structure. It is suggested that the bimodal distribution of tungsten grain size is attributed to the distribution of Y 2 O 3 during hydrogen reduction process and can be well avoided by controlling ρ(H + ).
研究领域:
材料科学
·
纳米材料
·
粉末冶金
·
无机非金属材料
·
功能材料
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2016
·Vol. 4
·期 11
·1829-1837
·
IF 5.359
Yucheng Liu,Jiankun Sun,Zhou Yang,Dong Yang,Xiaodong Ren,Hua Xu,Zupei Yang,Shengzhong (Frank) Liu
CH 3 NH 3 PbX 3 (MAPbX 3 )-based perovskite has attracted tremendous research efforts in the last few years. With the discovery that the HC(NH 2 ) 2 PbI 3 (FAPbI 3 ) perovskite offers even higher solar cell efficiency, better thermal stability, and broader optical absorption, it is expected that it will provide more excitement in optoelectronic applications including laser, LED, photodetector, etc. The development in preparing large Single-Crystalline Formamidinium-Perovskite FAPbI 3 using the inverse-temperature reactive crystallization process, and associated wafer-slicing process is presented. The availability of the large Single-Crystalline Formamidinium-Perovskite Wafer makes it possible to fabricate integrated circuits. An array of 153 photodetectors on a piece of thin wafer, demonstrating feasibility of mass production of integrated circuits on the perovskite wafer is designed and prepared. It is found that the wafer-based photodetector shows much superior performance, with 90 times higher photoresponse and broader optical absorption than its thin-film perovskite counterpart.
研究领域:
材料科学
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半导体物理
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光电子学
·
晶体生长
·
器件 fabrication
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Minghao Sun,Haoxiang Zhong,Shuren Jiao,Hanqi Shao,Lingzhi Zhang
Carboxymethyl chitosan (C-CTS) was firstly reported as a water soluble binder for LiFePO 4 cathode in Li-ion batteries. The electrochemical performances of LiFePO 4 cathode with C-CTS binder was investigated and compared with the conventional water-soluble sodium carboxymethyl cellulose (CMC) and the commercial non-aqueous polyvinylidene difluoride (PVDF). LiFePO 4 cathode with C-CTS exhibited a comparable cycling performance, but better rate capability than that of CMC and PVDF, retaining 65% capacity of C/5 at 5 C rate as compared with 55.9% and 39.4% for CMC and PVDF, respectively. In addition, LiFePO 4 cathode with C-CTS exhibited excellent cycling performance at 60 °C, retaining 91.8%/62.1% capacity after 80 cycles at 1 C/10 C, respectively.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子化学
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
·
IF 6.333
Bo Chen,Qiang Xu,Zhen Huang,Yanran Zhao,Shaojie Chen,Xiaoxiong Xu
A new class of copolymer electrolytes with tunable network structure is successfully designed and prepared via a facile one-pot reaction. The trimethylolpropane triglycidyl ether (TMPEG) is cross-linked with poly (ethylene glycol) diamine (NPEG) to create well-defined solid network polymer electrolyte (SNPE). The network structure could be tuned by changing the molar ratio of TMPEG and NPEG or the molecular weight of NPEG. The effects of molecular weight of NPEG and molar ratio of EO/Li + on the ionic conductivity are systematically investigated. The optimal electrolyte TMPEG-NPEG4K[2:1]-16:1 presents a maximum conductivity of 1.10 × 10 −4 S cm −1 under 30 °C, and an 18-fold ionic conductivity enhancement in that of PEO-based electrolyte. Furthermore, it also exhibits wide electrochemical window (0–5.4 V), excellent compatibility with metallic Li, and superior mechanical properties. The all-solid-state lithium batteries LiFePO 4 /Li are assembled with TMPEG-NPEG4K[2:1]-16:1 electrolyte, and present good cycling and rate performance under 60 °C. The initial discharge specific capacities of the batteries are 161.7 mAh g −1 at 0.2 C and 132.7 mAh g −1 at 1 C, and the capacity retention ratio can be retained at 90.6% and 90.5% after 100 cycles. This new copolymer electrolyte may become a promising candidate for applications in all-solid-state lithium battery.
研究领域:
材料科学
·
高分子化学
·
电化学
·
能源存储
·
固态离子学
·
锂离子电池
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2016
·Vol. 27
·期 11
·1501-1507
·
IF 1.823
Zhubo Liu,Bing Zhou,A.V. Rogachev,M.A. Yarmolenko
Polytetrafluoroethylene (PTFE) composite coatings doped copper acetate and polyurethane (PU) were prepared on rubber substrate by low-energy electron beam dispersion technique. The effects of dopant and glow discharge treatment on the surface morphology, structure and tribological properties of the coatings were investigated. The results showed that Cu–PTFE composite coatings form uniform surface and dense column structure with spherical aggregations under glow discharge treatment. PU coating shows the large size of protuberance structure but PU–PTFE coating presents spherical structure. Both of the coatings become relative dense and smooth after discharge treatment, and Cu–PU–PTFE composite coatings possess a smoother surface and lower polar component of surface energy. Cu doping weakens the crystallinity and ordering degree of composite coatings, but glow discharge increases the ordering degree and branched structure of C―H groups. Friction experiment indicated that Cu fails to improve the wear resistance of PTFE coatings but glow discharge treatment can do it. Cu–PU–PTFE coatings after discharge treatment have the higher wear resistance and lower coefficient of friction. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
材料科学
·
表面工程
·
高分子材料
·
摩擦学
·
等离子体物理
·
涂层技术
✓ 已验证
DOI
高影响因子
Small
·
2020
·Vol. 16
·期 38
·2003557
·
IF 11.459
Zheng Liu,Su Zhang,Zhipeng Qiu,Chao Huangfu,Lin Wang,Tong Wei,Zhuangjun Fan
Tin (Sn) is considered to be an ideal candidate for the anode of sodium ion batteries. However, the design of Sn-based electrodes with maintained long-term stability still remains challenging due to their huge volume expansion (≈420%) and easy pulverization during cycling. Herein, a facile and versatile strategy for the synthesis of nitrogen-doped graphene quantum dot (GQD) edge-anchored Sn nanodots as the pillars into reduced graphene oxide blocks (NGQD/Sn-NG) for ultrafast and ultrastable sodium-ion storage is reported. Sn nanodots (2–5 nm) anchored at the edges of “octopus-like” GQDs via covalent Sn O C/Sn N C bonds function as the pillars that ensure fast Na-ion/electron transport across the graphene blocks. Moreover, the chemical and spatial (layered structure) confinements not only suppress Sn aggregation, but also function as physical barriers for buffering volume change upon sodiation/desodiation. Consequently, the NGQD/Sn-NG with high structural stability exhibits excellent rate performance (555 mAh g −1 at 0.1 A g −1 and 198 mAh g −1 at 10 A g −1 ) and ultra-long cycling stability (184 mAh g −1 remaining even after 2000 cycles at 5 A g −1 ). The confinement-induced synthesis together with remarkable electrochemical performances should shed light on the practical application of highly attractive tin-based anodes for next generation rechargeable sodium batteries.
研究领域:
材料科学
·
电化学
·
纳米能源
·
储能材料
·
先进电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2024
·Vol. 53
·期 10
·6553-6562
·
IF 2.2
Zhang Yu,Ma Jianli,Chen Chen,She Yubin
In this work, non-stoichiometric Li 2(1+ x ) Mg 3 Ti 4 O 12 (L x MTO, x = 0.00–0.05) ceramics with excess lithium were prepared through a simple reaction sintering route to suppress lithium volatilization. According to the characterization of the phase composition and microscopic morphology of the pellets, single-phase L x MTO ceramics with a good microstructure were obtained. Excess lithium effectively inhibited the volatilization and optimized the morphology of the ceramics. A trend in relative density with an initial increase followed by a steep decrease was a predominant observation with the change in dielectric properties. The permittivity of the samples was dominated by the relative density and distortion of the [TiO 6 ] octahedron structure caused by Li + . The dielectric loss primarily originated from the refraction loss and scattering generated by pores, and the grain boundaries also contributed to the loss in the quality factor. Ultimately, at 1220°C, the Li 2.08 Mg 3 Ti 4 O 12 ceramics exhibited excellent microwave dielectric properties: ε r = 17.83, Q × f = 69,823 GHz and τ f = −18.19 ppm/°C.
研究领域:
材料科学
·
无机非金属材料
·
介电材料
·
陶瓷学
·
固态化学
·
电子材料
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 8
·547
·
IF 2.5
Geriletu,Gu Hao
Flexible silicone materials have excellent elastic properties and can maintain excellent structural stability under high-intensity repeated deformation. They are ideal materials for preparing piezoresistive flexible sensors. However, traditional silicone materials exhibit strong insulation properties. The solid block structure is also not conducive to improving sensitivity. Inspired by the irregular hole structure of Taihu Lake stone, this paper prepared a porous silica gel skeleton (rGO/CTAB/SG) based on reduced graphene oxide film coating, which was equipped with flexible interdigital electrodes to achieve electrical signal derivation. The “honeycomb” shaped sensing module prepared in this way achieves an extremely wide elastic deformation range (20-200%). In the pressure feedback layer, the rGO film is evenly coated on the SG surface, which greatly improves the device conductivity and sensing performance (high sensitivities of 89.4 kPa − 1 and 25.4 kPa − 1 are achieved within 0-30.2 kPa and 30.2–42 kPa, ultra-high durability under more than 22,000 load-unload cycles.) Numerical simulation analysis results confirmed that the structure of the flexible substrate SG prepared by this method maintained well when extreme deformation occurred, and no fracture or stress concentration occurred. As an elastic sensor, after being integrated with a microprocessor, it can easily monitor and analyze human body movement in real time. It has huge potential in areas such as daily training and health monitoring of athletes.
研究领域:
生物医学工程
·
柔性电子
·
运动医学
·
可穿戴传感器
·
力学传感
·
功能材料
✓ 已验证
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2011
·Vol. 32
·期 21
·1729-1734
·
IF 4.371
Juanping Hu,Xianfeng Wang,Bin Ding,Jinyou Lin,Jianyong Yu,Gang Sun
Electro-spinning/netting (ESN) as a cutting-edge technique evokes much interest because of its ability in the one-step preparation of versatile nano-fiber/net (NFN) membranes. Here, a controllable fabrication of polyurethane (PU) NFN membranes with attractive structures, consisting of common electrospun nanofibers and two-dimensional (2D) soap bubble-like structured nano-nets via an ESN process is reported. The unique nanoscaled NFN architecture can be finely controlled by regulating the solution properties and several ESN process parameters. The versatile PU nano-nets comprising interlinked nanowires with ultrathin diameters (5–40 nm) mean that the NFN structured membranes possess several excellent characteristics, such as an extremely large specific surface area, high porosity and large stacking density, which would be particularly useful for applications in ultrafiltration, special protective clothing, ultrasensitive sensors, catalyst support and so on.
研究领域:
材料科学
·
高分子化学
·
纳米技术
·
膜科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Yawei Song,Kuanjun Fang,Mohd Nadeem Bukhari,Kun Zhang,Zhiyuan Tang
Inkjet printability of dye-based inks including stability, jetting morphology, and color performance is difficult to maintain due to the strong dye molecular interaction. Herein, carboxyl-rich polymer nanospheres were introduced to the dye-based inks, forming a novel kind of multilayer dye/polymer nanospheres to enhance the inkjet printability. Disperse dyes were firstly loaded into poly (styrene-butyl acrylate-methacrylate) nanospheres at 95 °C, and then encapsulated by poly (styrene-methacrylate) polymer layer through seed polymerization to form multilayer structure. The results showed that hydrogen bonds were formed between disperse dyes and nanospheres, and the interaction was enhanced when more carboxyl groups were polymerized on nanosphere surface. Moreover, due to the high surface carboxyl group content, the stability was significantly improved in comparison with disperse dye suspension. After inkjet printing , the dye/nanosphere dispersion showed more stable droplet formation and higher color depth. Besides, because of the self-curing ability of polymer nanospheres, satisfactory fastness was obtained for practical application. The results from this study can promote the optimization of dye-based ink formulations, and show great potential in obtaining high quality inkjet printing products.
研究领域:
材料科学
·
高分子化学
·
表面化学
·
印刷电子学
·
功能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·Vol. 43
·期 3
·2969-2973
·
IF 2.758
Bing Xie,Haibo Zhang,Hao Kan,Sisi Liu,Ming-Yu Li,Zeyu Li,Shuai Zhu,Shiyong Qiu,Shenglin Jiang
This work demonstrates a highly efficient method for large-scale synthesis of elongated BaTiO 3 nanowires via a novel stirring hydrothermal process. Compared with conventional hydrothermal reaction , one-dimensional (1D) lead-free BaTiO 3 nanowires can be realized at an even lower temperature with a shorter dwelling time. Results suggest that the mechanical force-driven stirring process improved the diffusion and surface reaction rate of BaTiO 3 nanocrystal growth in the solution phase, apparently, leading to the growth of the BaTiO 3 nanowires via an oriented attachment mechanism. Meanwhile, to the best of our knowledge, this method is also the first reported protocol which is capable to grow elongated BaTiO 3 nanowires with length up to tens of micrometers. This research outcome provides a promising option for low cost, high-throughput fabrication of 1D nanostructure in respect of mass-manufacturing.
研究领域:
材料科学
·
纳米科技
·
无机合成
·
功能材料
·
铁电材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 16
·23258-23265
·
IF 5.532
Jianlong Chai,Yabin Zhu,Xing Gao,Tielong Shen,Lijuan Niu,Shufen Li,Peng Jin,Minghuan Cui,Zhiguang Wang
Al 2 O 3 /SiC ceramic composites with different SiC contents have been prepared by powder metallurgy at 1600 °C for 120 min at 30 MPa pressure. The effect of second phase particles on the microstructure and mechanical properties of composites have been studied. The results show that SiC particle has a significant impact on the matrix subjected to residual stress, and on the microstructure of the composites as well. The average grain size of alumina matrix decreases as the SiC particle content increases. Simultaneously, it has been found that the mechanical properties of the material are significantly enhanced in comparison with monolithic Al 2 O 3 . The highest strength and toughness are obtained when the SiC content is 15 vol%, and the values are 1237 MPa and 5.68 MPa m 1/2 , respectively. The mechanisms of strengthening and toughening have been discussed.
研究领域:
材料科学
·
陶瓷学
·
复合材料工程
·
固态物理
·
粉末冶金
✓ 已验证
DOI
高影响因子