|
| ||
|
|
||
CNT Network (cnt + network)
Selected AbstractsElectrically Addressable Hybrid Architectures of Zinc Oxide Nanowires Grown on Aligned Carbon NanotubesADVANCED FUNCTIONAL MATERIALS, Issue 15 2010Jong G. Ok Abstract The fabrication and characterization of hybrid architectures of ZnO nanowires (ZNWs) grown on organized carbon nanotubes (CNTs), by a two-step chemical vapor deposition (CVD) process involving CNT growth from a hydrocarbon source followed by ZNW growth using a Zn metal source, is reported. The ZNWs grow uniformly and radially from individual CNTs and CNT bundles, and the aligned morphology of the CNTs is not disturbed by the ZNW growth process. The nucleation and growth of ZnO crystals on CNTs are analyzed in relation to the classical vapor,solid mechanism. Importantly, the CNTs make uniform and distributed electrical contact to the ZNWs, with up to a 1000-fold yield advantage over conventional ZNW growth on a flat substrate. Hybrid ZNW/CNT sheets are fabricated by scalable CVD, rolling, and printing methods; and their electrical properties, which are governed by transport through the anisotropic CNT network, are characterized. Functional interaction between the ZNWs and CNTs is demonstrated by photoconductive behavior and photocurrent generation of the hybrid material under UV illumination. There is significant future opportunity to extend these processing methods to fabricate other functional oxides on CNTs, and to build devices that harness the attractive properties of ZNWs and CNTs with high volumetric efficiency over large areas. [source] Carbon Nanotube Junctions: Multibranched Junctions of Carbon Nanotubes via Cobalt Particles (Adv. Mater.ADVANCED MATERIALS, Issue 44 200944/2009) Junctions between different carbon nanotubes (CNTs) created using cobalt particles as central nodes (background) are demonstrated by Ming-Sheng Wang and co-workers on p. 4477. The process involves high-temperature electron irradiation of areas where a metal particle is located at the overlapping region of two CNTs. In situ transmission electron microscopy measurements show that the junctions are electrically conductive and mechanically robust. The extension of this technique towards creating more complicated structures, such as a 3D CNT network, is also depicted in the cover. [source] A Promising Approach to Enhanced Thermoelectric Properties Using Carbon Nanotube NetworksADVANCED MATERIALS, Issue 4 2010Chuizhou Meng Enhanced Seebeck coefficients and power factors , important for the conversion of heat to electrical energy , are obtained in polyaniline/carbon nanotube (PANI/CNT) composites in which PANI coats CNT networks (see figure). The values are several times larger than those of either of the individual components. This new approach has potential for synthesizing high-performance thermoelectric materials. [source] Electrical resistance variation of carbon-nanotube networks due to surface modification of glass substratePHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2010Eui Yun Jang Abstract This study presents the effect of the wettability between a glass substrate and carbon-nanotube (CNT) colloidal solution on the density of CNT networks in a dip-coating process. The surface roughness and the density of functional groups of the glass substrate were modified by using an oxygen-plasma treatment, and then we observed the density of CNT networks with respect to different surface conditions due to the surface modification. It is confirmed that the surface chemical property and the surface morphology of the glass substrate determines the density of CNT networks formed by the dip-coating method. The change of surface free energy induced by hydroxylation and hydration enhances the wettability between a glass substrate and CNT colloidal solution. Moreover, the effective area on which silanol groups can be formed is dependent on the roughness of the surface of the substrate. Eventually, the change of the surface free energy due to the hydroxylation, hydration, and surface roughness effect on the density of the coated CNTs, which determines the sheet resistance of CNT networks. [source] | ||||||||||