共查询到20条相似文献,搜索用时 878 毫秒
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化学镀法制备纳米Cu/Al复合粉末 总被引:8,自引:0,他引:8
为了改善超细铝粉的表面易氧化问题和微米级铝粉对推进剂的热分解催化作用不明显现象,以对推进剂具有良好催化作用的纳米Cu包覆金属Al表面.采用化学镀铜法对微米级铝粉表面进行镀覆,制备出纳米Cu粒子在超细Al颗粒表面包覆完整的Al-Cu核壳式复合粉末,并利用正交实验优化镀液组分及镀覆工艺条件.利用XRD、SEM、EDX等仪器,对复合粉末的形貌、物相结构及表面成分进行分析,结果表明铝粉表面包覆一层致密的纳米铜层,这种纳米层是由粒度约为18.83nm的晶态析出的纳米铜组成. 相似文献
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纳米Fe粒子包覆微米Al复合材料的制备与表征 总被引:2,自引:0,他引:2
采用置换法,通过在溶液中引入F-子,实现了弱酸性条件下Fe纳米粒子在微米Al粉表面定量、快速地化学沉积,制备出具有核壳结构的Fe/Al微纳米复合粒子.将该复合粒子中的Al核用盐酸溶蚀后得到由纳米Fe粒子组成的空心球壳.利用SEM、EDS、XRD、BET和TG/DSC对产物进行了相应地表征,结果表明,微米Al核表面被一层粒径约为30~60nm的Fe纳米粒子致密包覆,Fe/Al复合粉体的比表面积达到11.993m2/g较包覆前的1.082m2/g增加了11倍,且Fe/Al微纳米复合粉体与O2反应的活性明显高于原料Al粉. 相似文献
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核壳结构纳米Ni/Al复合粉末的制备 总被引:2,自引:0,他引:2
在含氟离子的水溶液中,采用Al粉直接置换还原Ni盐的方法,实现了纳米Ni在Al粉表面上的快速化学沉积,制备出核壳结构的Ni/Al复合粉末。探讨了反应的过程,利用SEM、XRD、BET等测试手段对复合粉末进行了微观测试和表征。结果表明:Al粉表面连续、均匀包覆了由晶粒大小约20.6nm的Ni纳米颗粒组成的壳层。 相似文献
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在低温条件(80℃)下,以钛酸丁酯为原料,利用胶溶–回流法在氧化铝粉体表面制备了纳米TiO2颗粒.通过扫描电镜、X射线衍射、X光电子能谱仪、BET等检测手段对复合颗粒的表面形貌、包覆层相组成、比表面积等进行了表征.结果表明,纳米TiO2颗粒在微粉表面形成纳米薄膜修饰层,包覆层主要为锐钛矿型相,表面纳米化修饰后氧化铝粉体表面的粗糙度显著增加,比表面积较包覆前提高了30倍以上.将经表面纳米化修饰后的微粉应用于以有机硅改性环氧树脂为基体的耐磨涂层中,其磨损失重仅为包覆前复合耐磨涂层的55%,耐磨性显著提高,并初步讨论了复合耐磨涂层的摩擦磨损性能. 相似文献
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硅酸铝- 硅灰石复合粉体材料的制备及其在聚丙烯中的应用 总被引:3,自引:0,他引:3
以硅灰石为原料,以硫酸铝和水玻璃为包覆剂,采用化学沉淀法,制备了一种纳米硅酸铝- 硅灰石复合粉体材料;用氨基硅烷对该材料进行表面改性后填充聚丙烯制备了聚丙烯复合材料。采用 SEM、BET氮吸附比表面积仪、粒度仪、白度仪、XRD、EDX、FTIR等测试方法对复合及表面改性粉体材料进行了表征,并探讨了氨基硅烷改性复合粉体的机制。结果表明:硅灰石表面均匀地包覆了一层纳米硅酸铝,白度由90.5提高到92.5,比表面积由1.41m2/g提高到4.78m2/g,晶粒平均尺寸为54 nm;填充 PP质量分数40%的改性复合粉体可以使纯PP的拉伸强度由17.81 MPa 提高到 21.97 MPa,弯曲强度由23.72 MPa 提高到39.20 MPa,热变形温度由65.7℃ 提高到94.3℃。 相似文献
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刘红霞徐阳周昌兵韦春樊新 《高分子材料科学与工程》2017,(11):166-170
首先通过原位聚合的方法制备聚苯胺(PANI)包覆纤维素纳米晶(CNC)(CNC@PANI)纳米复合物,进而采用共混法制备CNC@PANI与rGO的复合电极材料(CNC@PANI/rGO)。研究不同苯胺与CNC的用量比对所得复合电极材料的结构形貌和电化学性能的影响。采用扫描电镜、X射线衍射、红外光谱以及电化学工作站等测试手段对制备的复合电极材料的结构形貌、电化学性能进行分析表征。结果表明,PANI成功地包覆在CNC的表面,且PANI通过在CNC表面的包覆,可明显改善其分散性和比表面积,以及与石墨烯的复合效果。CNC@PANI-1/rGO复合电极材料在20mV/s扫描速率下的比电容可高达309F/g,远远高于PANI/rGO复合电极材料的155F/g。 相似文献
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This paper describes procedures for the template synthesis of magnetically controlled, large surface area Fe3O4/SiO2 nanocomposites using sodium oleate as a template. The structure and magnetic properties of the nanocomposites have been investigated
in relation to SiO2 content and the way in which sodium oleate had been added to the solution. The largest specific surface area (up to 400 m2/g) was reached when the nanocomposites were fabricated using magnetic fluids. The synthesized materials were tested as adsorbents. 相似文献
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Facile synthesis and characterization of novel nanocomposites of titanate nanotubes and rutile nanocrystals 总被引:1,自引:0,他引:1
The nanocomposites of one-dimensional (1D) titanate nanotubes and 0D rutile nanocrystals were fabricated by hydrothermal treatment of bulky rutile TiO2 powders in a 10 M NaOH solution without using any templates and catalysts. The as-prepared samples were characterized with transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, Fourier transform infrared spectroscopy (FTIR), UV–visible spectrophotometry (UV–vis), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that many small rutile nanocrystal particles of about 5 nm could uniformly attach to the outer surface and in the inner of the titanate nanotubes, forming an interesting and novel nanocomposite structure. Adjusting reaction time could control the amount of rutile nanoparticles in the nanocomposites. With increasing reaction time, the specific surface areas, porosity, pore volume, UV absorption and band gap energies of the nanocomposites gradually increased due to the fact that rutile particles were steadily turned into the tubular nanocomposites, finally completely formed titanate nanotubes. 相似文献
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Koon-Yang Lee Puja Bharadia Jonny J. Blaker Alexander Bismarck 《Composites Part A》2012,43(11):2065-2074
“Hairy” bacterial cellulose coated sisal fibres were created using a simple slurry dipping process. Neat sisal fibres were coated with BC to create (i) a dense BC coating around the fibres or (ii) “hairy” fibres with BC oriented perpendicular to the fibre surface. These fibres were used to produce hierarchical sisal fibre reinforced BC polylactide (PLLA) nanocomposites. The specific surface area of the BC coated fibres increased when compared to neat sisal. Single fibre tensile tests revealed no significant difference in the tensile modulus and tensile strength of “hairy fibres”. However, when sisal fibres were coated with a dense BC layer, the mechanical fibre properties decreased. The tensile, flexural and visco-elastic properties of the hierarchical PLLA nanocomposites reinforced by both types of BC coated sisal fibres showed significant improvements over neat PLLA. 相似文献
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Preparation and tribological properties of graphene oxide/nitrile rubber nanocomposites 总被引:3,自引:0,他引:3
Graphene oxide (GO)/nitrile rubber (NBR) nanocomposites with various contents of GO were prepared by a solution-mixing method,in
this study. The GO sheets were exfoliated from natural fake graphite by an improved Hummers method and could be further dispersed
homogeneously in NBR matrix. The thickness and size of the GO sheets were observed by atomic force microscopy and transmission
electron microscopy. The tribological properties of the GO/NBR nanocomposites were evaluated on a ring-block MRH-3 wear tester
under dry sliding and water-lubricated conditions. The worn surface morphologies of the GO/NBR nanocomposites were observed
by a scanning electron microscopy. It was found that under dry sliding, both the friction coefficient (COF) and specific wear
rate of the nanocomposites decreased dramatically at first, then increased with increasing GO contents, while under water-lubricated
condition, both the COF and specific wear rate of the nanocomposites decreased with increasing GO contents. Finally, the
friction and wear mechanisms of the GO/NBR nanocomposites were tentatively proposed. 相似文献
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Qiao H Li J Fu J Kumar D Wei Q Cai Y Huang F 《ACS applied materials & interfaces》2011,3(9):3704-3708
In this study, we successfully prepare SnO(2) nanoparticles inside the pore channels of CMK-3 ordered mesoporous carbon via sonochemical method. The content of SnO(2) is 17 wt % calculated according to the energy-dispersive X-ray spectroscopy (EDS) result. CMK-3 with 17 wt % loading of SnO(2) nanoparticles has a large specific surface area and pore volume. Electrochemical performance demonstrates that the ordered SnO(2)/CMK-3 nanocomposites electrode possesses higher reversible capacity and cycling stability than that of original CMK-3 electrode. Moreover, the ordered SnO(2)/CMK-3 nanocomposites electrode also exhibits high capacity at higher charge/discharge rate. The improved electrochemical performance is attributed to the nanometer-sized SnO(2) formed inside CMK-3 and the large surface area of the mesopores (3.4 nm) in which the SnO(2) nanoparticles are formed. 相似文献
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The authors present the first reported use of vertically oriented titanium oxide nanotube/polypyrrole (PPy) nanocomposites to increase the specific capacitance of TiO2 based energy storage devices. To increase their electrical storage capacity, titanium oxide nanotubes were coated with PPy and their morphologies were characterized. The incorporation of PPy increased the specific capacitance of the titanium oxide nanotube based supercapacitor system, due to their increased surface area and additional pseudo-capacitance. 相似文献
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We present a straightforward procedure to prepare composite photoanodes which consisted of TiO2 rutile nanorods/anatase nanoparticles synthesized under hydrothermal conditions, with the ratio of rutile to anatase controlled simply by adjusting the volume of nitric acid. The as-prepared TiO2 composites exhibited high specific surface area, light-scattering effect, and good crystallinity. The dye-sensitized solar cells (DSCs) using the TiO2 composites showed higher short-circuit photocurrent and overall conversion efficiency than the DSC from pure-anatase nanoparticles. The highest conversion efficiency was achieved from the DSC based on TiO2 nanocomposites with 24 wt% rutile nanorods, which was attributed to improved light harvesting caused by the enhancement of specific surface area and scattering effect from rutile nanorods. 相似文献
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TiO2 nanostructures with different morphologies (spherical, tube, leaf-like and flower-like particles) were synthesized via a facile hydrothermal process. Polycaprolactone (PCL)/10 vol.% TiO2 nanocomposites were prepared by solvent casting methods. In vitro bioactivity of the nanocomposite films was examined by immersion in the simulated body fluid (SBF) for up to 28 days. It was found that the morphology of titania nanostructures significantly influence the in vitro bioactivity of PCL/TiO2 nanocomposites. This observation was attributed to the amount of anatase phase and the specific surface area of the TiO2 nanostructures, which provide high surface exposure to SBF. 相似文献
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Nasrin Ghassemi Saied Saeed Hosseiny Davarani Hamid Reza Moazami 《Journal of Materials Science: Materials in Electronics》2018,29(15):12573-12583
In this work, CuFe2O4/CuO nanocomposites have been synthesized by galvanostatic cathodic electrodeposition. The obtained nanocomposites were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier Transform Infrared, and Brunauer–Emmett–Teller surface area analysis. The electrochemical properties of CuFe2O4/CuO nanocomposites were evaluated by cyclic voltammetry, galvanostatic charge–discharge cycling, and electrochemical impedance spectroscopy in 1.0 M KOH. The CuFe2O4/CuO nanocomposites have shown the high specific capacitance of 322.49 F g?1 at the scan rate of 1 mV s?1. After 5000 cycles, 92% of this specific capacitance was retained. Although the prepared nanocomposite has shown a mediocre specific capacitance compared to other metal oxide-based materials, the low cost of the starting materials and the ease of preparation make this nanocomposite a good candidate for supercapacitor applications. 相似文献