共查询到19条相似文献,搜索用时 640 毫秒
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采用电子扫描显微镜(SEM)表征过氧化氢(H_2O_2)蚀刻的银纳米线表面形貌,采用紫外-可见(UV-vis)吸收光谱、荧光光谱以及拉曼光谱研究蚀刻后银纳米线的表面等离激元特性。结果表明:H_2O_2可有效蚀刻银纳米线表面形貌,与未蚀刻的银纳米线相比,蚀刻后的银纳米线平均直径减小,表面形成纳米凹槽以及立方状的银纳米粒子,银纳米线表面等离激元共振吸收峰强度增大,并呈现宽化。由于蚀刻后的银纳米线光电耦合增强,导致表面的电磁场强度增大,对罗丹明B(RB)探针分子的荧光辐射增强16.8倍,对RB探针分子的拉曼散射信号增强约6.2×105倍。这对于纳米金属表面增强光谱具有积极的应用意义。 相似文献
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《稀有金属材料与工程》2016,(Z1)
通过提拉成膜法制备了银纳米线阵列,以罗丹明B(RhB)染料分子为荧光发光基体,研究了银纳米线阵列对罗丹明B荧光性能的影响。结果表明:金属银纳米线阵列薄膜中的银纳米线定向分布状态、银纳米线分散浓度以及偏振激发光入射状态都会对RhB荧光性能产生影响。 相似文献
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用连续三脉冲(氧化、成核和生长)电势或电流在高定向石墨表面电沉积钯合金纳米线阵列。研究了电沉积工艺对合成纳米线的成分、尺寸及形貌的影响。在含高浓度铵离子的钯镍和钯银氨配合物系统中合成钯合金纳米线阵列有利于钯镍和钯银合金的共沉积,提高电沉积溶液的导电性能。控制电势合成法能获得成分均匀的纳米线阵列,但控制电流法能获得线径均匀的线条。在-1.5~-1.4 V电势下成核5~1000 ms,在-0.5~-0.25 V或-60~-20μA/cm2下生长可得到成分均匀的钯合金,线条尺寸均匀、连续、平行和分离的镍含量为8%~15%的钯镍合金纳米线和银含量为16%~25%的钯银合金纳米线阵列。 相似文献
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银纳米线由于具有独特的核壳结构,被用于构建神经形态纳米线网络。以经典多元醇法为模板,设计正交实验合成了一系列核壳结构银纳米线,分析了反应温度、聚乙烯吡咯烷酮(PVP)的相对分子量、PVP用量和卤离子含量等因素对银纳米线长度、直径及核壳结构微观特征的具体影响。结果表明,相对分子质量高的PVP更适合制备具有AgNWs-Ag核壳结构的银纳米线;由银纳米线组成的神经形态纳米线网络表现出类似人工突触行为的忆阻响应曲线,其神经形态特性受银纳米线核壳结构微观特征影响,并表现出明显的湿度依赖特性。 相似文献
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以聚乙烯基吡咯烷酮(PVP)为稳定剂,聚乙二醇(EG)为还原剂,采用聚醇法[1]制备了银纳米线.根据硝酸银/PVP比例的不同制备了4种类型的银纳米线样品,其中样品D直径最均匀,杂质含量最低.通过改变硝酸银/PVP比例、加入速率和PVP分子量,可对对银纳米线的长度和直径进行控制,得到了小直径(17~100 nm)、大长度(30 nm到100μm以上)的银纳米线.采用XRD、SEM、TEM和紫外-可见光谱对银纳米线的结构进行了表征.采用不同径长比纳米银线混合,以聚对苯二甲酸二乙酯(PET)和玻璃为衬底,分别使用可扩展层压辅助溶液法和旋转涂布法制备了2种透明导电薄膜,其方阻分别为17和26?/sq,透光率分别为88%和80%. 相似文献
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以聚乙烯吡咯烷酮(PVP)作为表面活性剂,利用乙二醇还原体系合成了具有不同形貌的银纳米结构,并详细分析了这些银纳米结构的形貌和结构特征。通过紫外-可见吸收光谱检测分析了不同形貌银纳米结构的光学性质;并从实验和理论上详细研究了单根银纳米线的光波导特征。实验表明,单根Ag纳米线是非常有效的波导腔,入射光可通过存在于Ag纳米线表面的表面等离激元辅助在纳米尺度上有效地输运到纳米线最末端而再发射。 相似文献
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With rapid progress in nanotechnology, nanostructured materials have come closer to our life. Single-component nanowires are actively investigated because of their novel properties, attributed to their nanoscale dimensions and adjustable aspect ratio, but their technical limitations cannot be resolved easily. Heterostructured nanomaterials gained attention as alternatives because they can improve the existing single-component structure or add new functions to it. Among them, barcode nanowires (BNWs), comprising at least two different functional segments, can perform multiple functions for use in biomedical sensors, information encoding and security, and catalysts. BNW applications require reliable response to the external field. Hence, researchers have been attempting to improve the reliability of synthesis and regulate the properties precisely. This article highlights the recent progress and prospects for the synthesis, properties, and applications of metallic BNWs with focus on the dependence of the magnetic, optical, and mechanical properties on material, composition, shape, and microstructure. 相似文献
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采用光学显微镜、电子背散射衍射技术、维氏硬度计和电化学工作站等研究了轧制银铜板在退火过程中的组织、织构演变规律及其对维氏硬度、耐腐蚀性能的影响。结果表明:轧制银铜板退火时,晶粒形态由轧态的长条状演变为等轴晶组织,且平均晶粒尺寸增大,织构类型由铜型织构、黄铜型织构、S织构和R织构等形变织构演变为立方织构和{025}<001>等退火织构;随退火温度的升高,银铜板维氏硬度减小,银铜板小角度晶界含量降低,∑3晶界含量升高,耐腐蚀性能先减弱后增强。银铜板在300 ℃保温10 min时,立方织构含量最多,硬度为60 HV0.3,耐腐蚀性能较好。 相似文献
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利用激光诱导换膜的方法在氧化钛基体上制备出了银铜双金属薄膜,通过控制激光加工的参数和银铜成分制备出样品。用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、高分辨率透射电子显微镜(HRTEM)和J-V曲线分别对加工前后样品的结构、形貌及光伏性质进行了表征。结果表明:随着溶液中Cu2+浓度的增加,在ITO玻璃上所制备的银铜纳米枝晶的尺寸减小;利用激光诱导换膜工艺,可以在氧化钛基体上制备出银铜双金属薄膜;相比氧化钛膜,在氧化钛膜上沉积银铜双金属薄膜的光阳极具有更高的短路电流密度和开路电压;随着激光加工功率的增大,氧化钛膜上的银铜颗粒变小,光阳极的短路电流密度和开路电压均有增大,但是当激光加工功率很大时,其开路电压变小;在同一激光加工功率下,随着银铜双金属薄膜中银含量的增大,其短路电流密度和开路电压均有增大。 相似文献
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《Acta Materialia》2007,55(9):3007-3014
In response to a growing need for metal-oxide nanotubes and nanowires for nanoelectronic applications and size-effect studies, crystalline nanotubes and nanowires in a range of metal oxides have been synthesized at near-ambient conditions and without the application of heat treatments, pressure or an external electric field. Specifically, the mechanisms of formation of crystalline TiO2 nanotubes and nanowires from flourine-based liquid precursors inside anodic aluminum oxide templates have been elucidated. This method can be extended to synthesizing nanotubes/nanowires of other crystalline metal oxides, such as ZrO2, SnO2 and FeOOH. Using sequential deposition, TiO2/ZrO2 coaxial nanotubes have been synthesized. In principle, the methods outlined here could be used to fabricate crystalline nanotubes and nanowires of tailored dimensions in other metal oxides. The ability to synthesize, at near-ambient conditions, crystalline metal-oxide nanotubes and nanowires of tailored geometries represents a clear advantage in terms of minimal equipment requirements, low cost and possible incorporation of biomolecules and temperature-sensitive moieties. 相似文献
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铜-低碳钢钎焊接头的耐蚀性评价 总被引:3,自引:0,他引:3
通过动态挂片腐蚀实验、宏观和金相组织观察、SEM 及能谱分析等方法对采用Cu-Zn钎料、Ag-Cu钎料、Cu-P钎料钎焊的无氧纯铜-低碳钢管钎焊 接头的耐蚀性能进行了评价分析.结果表明:采用Cu-P钎料时钢和钎缝间出现裂纹,接头遭 受腐蚀后铜管内壁普遍腐蚀,同时钎缝因腐蚀而开裂;Cu-Zn钎缝成型好,但钎缝 本身出现由于金相组织发生选择性腐蚀而引起的局部蚀坑,铜管对应处也出现明显减薄性腐 蚀;Ag-Cu钎料所焊接头成型好,接头各处腐蚀轻微.建议采用Ag-Cu钎料进行铜-低碳钢的 钎焊. 相似文献
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一维金纳米材料的研究进展:Ⅱ.金纳米棒(丝)和金纳米粒子/碳纳米管复合材料的合成和组装 总被引:1,自引:0,他引:1
金纳米棒的光学性质和潜在应用在第一部分已经做了介绍,本部分将对金纳米棒和金纳米粒子/碳纳米管复合材料的合成和组装研究进行综述,包括:金纳米棒(或丝)的各种合成方法;棒的形状转化;自组装纳米结构和金纳米粒子/碳纳米管复合物的研究. 相似文献
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Large-scale CuO nanowires were in situ grown on Cu substrate by a very simple catalyst-free thermal oxidation process in atmosphere. The structure characterization revealed that these nanowires are monoclinic structured single crystallites with mean diameters of 60–200 nm. The effects of growth time and temperature on the morphology of the nanowires were investigated. It is found that the growth time has an important effect on the length and density of the nanowires, whereas the growth temperature has a distinct influence on the nanowire diameter. Different from the vapor–solid (V–S) mechanism, the growth of nanowires is found to be based on the Cu ion diffusion. The ethanol-sensing properties of these CuO nanowires were also studied based on a self-designed prototype and the results indicated that these large-scale nanowires are indeed a good candidate for gas-sensing applications. 相似文献