非晶碳和碳纳米管混合薄膜的场发射性能

利用微波等离子体化学气相沉积法在不锈钢衬底上直接合成非晶碳和碳纳米管混合薄膜.采用氢气和甲烷作为反应气体,流量分别为100和16sccm.沉积室内的压强为5.0kPa.利用场发射扫描电镜(SEM)和喇曼谱(Raman)对制备的薄膜的结构和形貌进行了分析.场发射实验在5×10-5Pa的真空下进行.实验结果表明:制备的非晶碳和碳纳米管混合薄膜开启电场较低,仅有0.9V/μm;在电场为3.7V/p.m时电流密度达到4.0mA/cm2,发射点密集,分布均匀.表明此种材料是一种优良的场发射冷阴极材料.     

非晶碳和碳纳米管混合薄膜的场发射性能

利用微波等离子体化学气相沉积法在不锈钢衬底上直接合成非晶碳和碳纳米管混合薄膜.采用氢气和甲烷作为反应气体,流量分别为100和16sccm.沉积室内的压强为5.0kPa.利用场发射扫描电镜(SEM)和喇曼谱(Raman)对制备的薄膜的结构和形貌进行了分析.场发射实验在5×10-5Pa的真空下进行.实验结果表明:制备的非晶碳和碳纳米管混合薄膜开启电场较低,仅有0.9V/μm;在电场为3.7V/p.m时电流密度达到4.0mA/cm2,发射点密集,分布均匀.表明此种材料是一种优良的场发射冷阴极材料.     

热解碳基C/C复合材料纤维--基体界面的精细结构

采用JEM-2010型高分辨透射电镜考察了热解碳基碳/碳复合材料的纤维-基体界面结构.实验发现,由化学气相渗透工艺所获得的热解碳并非仅与碳纤表面进行单一的机械粘合,也不是一个简单平面.其间存在具有感应结构的界面层,它是受碳纤维表面微晶感应而形成的由基本平行于表面且更为细小的微晶所组成的厚约数纳米至数十纳米的过渡层,碳纤维微晶越大,取向性越好,则界面层的厚度也越大,取向性也相应提高.由此可定性解释高模量碳纤维与热解碳粘合效果弱于高强碳纤维.     

基于MEMS工艺的碳纳米管(碳纳米纤维)铜微异型触点

一类为保护MEMS微继电器、提高它们使用寿命,而设计生产的微异型触点.该类微异型触点利用MEMS工艺,对铜基碳纳米管及碳纳米纤维复合电镀层进行细微图形化加工而成.一系列测试表明,铜基碳纳米管及碳纳米纤维复合电镀层本身具有良好的电接触性能,而利用MEMS工艺表面细微图形化加工后的微异型触点,比未经图形化加工的复合电镀层及纯铜触点具有更好耐电弧磨损性能.     

粒状活性碳过滤器与活性碳纤维过滤器的性能比较

本文重点对粒状活性碳过滤器和活性碳纤维过滤器在过滤水和空气时的性能进行了对比。同时对比了粒状活性碳和活性碳纤维的特性及结构,并说明了活性碳纤维具有粒状活性碳不可比拟的优点。对活性碳纤维过滤器的发展前景进行了展望,从而指出了活性碳纤维过滤器的经济性及其推广的可能性和必然性。     

Carbon Nanoparticles on Carbon Fabric for Flexible and High‐Performance Field Emitters

Carbon nanoparticles (CNPs) are grown on flexible carbon fabric via a simple and low‐cost flame synthesis process. The entire struture of the carbon fabric substrate retains its high flexibility after the growth of CNPs and can even be rolled‐up and twisted to a large degree without affecting the electric characteristics. No appreciable changes in the conductance can be observed under different bending curvatures after hundreds of bending cycles. The thermal conductivity of the carbon fabric with CNPs is about 2.34 W m^?1 K^?1, about one order of magnitude higher than that of most polymer substrates. The field emitter fabricated using the structure has a low threshold electric field of around 2.8 V μm^?1, and a high field emission current density of 108 mA cm^?2, which is about two to four orders of magnitude higher than that of most polymer substrate‐based flexible CNT field emitters. These results indicate that CNPs on carbon fabric have potential applications in flexible electronics devices and displays.     

Tailored Assembly of Carbon Nanostructures: Tailored Assembly of Carbon Nanotubes and Graphene (Adv. Funct. Mater. 8/2011)

This Feature Article reviews recent progress in the tailored assembly of carbon nanotubes and graphene into three‐dimensional architectures with particular emphasis on our own research employing self‐assembly principles. Carbon nanotubes and graphene can be assembled into macroporous films, hollow spherical capsules, or hollow nanotubes, via directed assembly from solvent dispersion. This approach is cost‐effective and beneficial for large‐scale assembly, but pre‐requests stable dispersion in a solvent medium. Directed growth from a nanopatterned catalyst array is another promising approach, which enables the control of morphology and properties of graphitic materials as well as their assembly. In addition, the aforementioned two approaches can be synergistically integrated to generate a carbon hybrid assembly consisting of vertical carbon nanotubes grown on flexible graphene films. Tailored assembly relying on scalable self‐assembly principles offer viable routes that are scalable for mass production towards the ultimate utilization of graphitic carbon materials in nanoelectronics, displays, sensors, energy storage/conversion devices, and so on, including future flexible devices.     

碳纳米管及其制备技术

介绍了碳纳米管及其制备技术的国内外最新研究进展,分析了碳纳米管材料的研究现状,并对碳纳米管材料未来的发展方向进行展望。     

低碳认证简析

该文对目前国际上现有的低碳认证的两种类型进行了介绍,并对认证得必要性、认证的存在问题及发展进行了深入浅出的阐述,以期对相关企业开展低碳认证提供思考和借鉴.     

碳纳米管制备及其生长机制研究

采用乙醇催化燃烧法,以钴盐作为催化剂先体、薄铜片作为基底制备碳纳米管。分别以氯化钴、硝酸钴和硫酸钴作为催化剂先体,研究了不同催化剂先体对碳纳米管生长的影响;利用扫描电镜,透射电镜对碳纳米材料的形貌和结构进行了表征,研究了不同钴盐的催化剂先体对碳纳米管形态与结构的影响,讨论了碳纳米管的生长机制。实验发现,其他制备条件相同,当催化剂先体为氯化钴时,碳纳米管与大量絮状杂质缠绕在一起;当催化剂先体为硝酸钴时,碳纳米管容易形成弯曲、不规则的波浪形结构;而当催化剂先体为硫酸钴时,实验所得的碳纳米材料几乎全为取向规则、直径均一的碳纳米纤维,只观察到少量碳纳米管。     

碳纳米管制备及其生长机制研究

采用乙醇催化燃烧法，以钴盐作为催化剂先体、薄铜片作为基底制备碳纳米管。分别以氯化钴、硝酸钴和硫酸钴作为催化剂先体，研究了不同催化剂先体对碳纳米管生长的影响；利用扫描电镜，透射电镜对碳纳米材料的形貌和结构进行了表征，研究了不同钴盐的催化剂先体对碳纳米管形态与结构的影响，讨论了碳纳米管的生长机制。实验发现，其他制备条件相同，当催化剂先体为氯化钴时，碳纳米管与大量絮状杂质缠绕在一起；当催化剂先体为硝酸钴时，碳纳米管容易形成弯曲、不规则的波浪形结构；而当催化剂先体为硫酸钴时，实验所得的碳纳米材料几乎全为取向规则、直径均一的碳纳米纤维，只观察到少量碳纳米管。