共查询到18条相似文献,搜索用时 78 毫秒
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转换垂直阵列式碳纳米管基底的研究 总被引:3,自引:1,他引:2
描述了一种将阵列式排列的碳纳米管膜完整地从沉积基底上逐层分离组装到新基底的技术。用扫描电镜研究了被分离的碳纳米管膜的形貌、黏结层的特点,并且对被分离的膜和膜与新基底的导电特性分别做了测试。电镜形貌分析表明构成碳纳米管膜的碳纳米管在被分离后可以保持原来的形貌,也可以呈弯曲状,这取决于分离膜时作用于膜表面的压力。电阻测试表明膜的表面电阻为10Ω,而膜与基底的电阻在有黏结层条件下小于0.1Ω。 相似文献
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酞菁裂解法制备定向碳纳米管阵列及其场发射性能研究 总被引:1,自引:0,他引:1
碳纳米管作为一种新型的光电材料有着广泛的应用,可用于平板显示器中的电子发射器件。定向碳纳米管阵列是碳纳米管的一种取向形态,具有其独特的性质。与缠绕无序的碳纳米管相比,定向碳纳米管更易分散、测量和应用。文章在低压条件下采用酞菁铁高温裂解法,在800~1000℃,以石英玻璃为基底,制备了大面积高度定向的碳纳米管。通过SEM和TEM对定向碳纳米管的结构进行分析。结果表明该法制备的碳纳米管长20μm,管径40~70nm,为竹节状结构的多壁碳纳米管。实验中发现系统真空度和生长温度都对定向碳纳米管生长有影响。通过对该碳纳米管进行场发射测试,结果表明此定向碳纳米管的开启电压仅为0.67V.μm-1(I=1μA),阈值电压为2.5V.μm-1,具有良好的场发射性能。 相似文献
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单壁碳纳米管(Single-walled carbon nanotube,SWCNT)有许多异常的电特性,要完全实现其在实际电子系统中的潜在应用价值,需要在器件与电路的结合上有不断创新的方法。由于SWCNT在电子学上分为金属型和半导体型两大类,其中每一大类根据手性的不同在电特性上又各有差异,再加上要合成或合成后分离出单一手性的SWCNT,目前的技术还存在相当大的难度。结合化学气相沉积中的控制生长、控制转移排列整齐有序的SWC-NT阵列与微加工工艺等方法,将SWCNT阵列作为一个器件单元来进行测试,测试结果显示了一定的场效应特性。 相似文献
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The field emission behavior of aligned carbon nanotubes (CNTs) is remarkably improved by decorating their surfaces with Ti nanoparticles through a sputtering process. The CNT/Ti(4 nm) sample shows a low turn-on field of 0.63 V/μm at 10 μA/cm2, low threshold field of 1.06 V/μm at 1 mA/cm2, and maximum field emission current density of 23 mA/cm2 at 1.80 V/μm. The enhanced field emission properties of the CNT/Ti samples are attributed to the added defect sites and Ti nanoparticles, which increase the field enhancement factor and density of emission sites. Stability measurements indicate that the Ti coating, which acts as a protective layer, also strengthens the field emission stability of the CNT arrays. Moreover, the extent of hysteresis in the current–voltage sweep highly depends on the voltage-sweep speed. 相似文献
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Savita P. Somani Prakash R. Somani A. Yoshida M. Tanemura S.P. Lau M. Umeno 《Solid-state electronics》2008,52(6):941-945
Vertically aligned carbon nanofibers (CNF) and multiwalled carbon nanotubes (MWCN) were synthesized from camphor by catalytic thermal chemical vapor deposition on Co and Co/Fe thin films (for CNF) and on silicon substrates using a mixture of camphor and ferrocene (for MWCN). CNF and MWCN were studied by scanning and transmission electron microscopy, visible Raman spectroscopy, X-ray diffraction in order to get insight into the microstructure and morphology of these materials. Field electron emission study indicates turn-on field of about 1.52, 2.3 and 4.3 V/μm for MWCN, Co/CNF and Co/Fe/CNF films, respectively; and threshold field of about 2.48, 3.1 and 6 V/μm, respectively. Our study indicates a better performance for field electron emission compared with some of the earlier published reports which might be due to higher aspect ratio, good graphitization and suitable density. 相似文献
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In this study, varying weight percentages of multiwalled carbon nanotubes were successfully incorporated into 95.8Sn-3.5Ag-0.7Cu
solder to synthesize novel lead-free composite solders. The composite solders were synthesized using a powder metallurgy route
consisting of blending, compaction, sintering, and extrusion. The extruded materials were then characterized for their physical,
thermal, and mechanical properties. With the addition of increasing weight percentage of carbon nanotubes, the composite solders
experienced a corresponding decrease in density values and an improvement in wetting properties. The melting temperatures
of the composite solders were found to be unchanged with additions of carbon nanotubes. However, improvements in the mechanical
properties, in terms of microhardness and tensile properties, were observed with increasing weight percentages of carbon nanotubes. 相似文献