Suspended bridge-shaped carbon nanotube (CNT) has great potential in nano-electromechanical systems, highly-sensitive sensors, various nanodevices and so on. However, complex processing largely restricts its practical applications. This work presents a novel laser comb (Laco) effect, stimulating a simple and effective fabrication strategy to achieve aligned suspended CNTs, which are bridge-shaped, direction-controlled, easily-patterned and all-carbon based.
View Article and Find Full Text PDFCarbon nanotubes are considered as great candidates for atomic force microscopy (AFM) probes because of their high aspect ratio and outstanding mechanical properties. In this work, we report that a conical AFM probe can be fabricated with arc discharge prepared multiwalled carbon nanotubes (MWCNTs) with an individual MWCNT at the apex by dielectrophoresis. The amplitude-displacement curve of the conical MWCNT probe demonstrates that this structure can remain stable until the force exerted on it increases to 14.
View Article and Find Full Text PDFMolecular magnets are demonstrated to provide a promising way to realize nanometer-scale structures with a stable spin orientation. Herein, first a description of conventional molecular magnets coupled with sp carbon materials, such as carbon nanotubes and graphenes, is given. Then, progress on ferromagnetism in sp carbon nanomaterials due to the existence of defects or topological structures as the spin units, which makes the sp materials themselves act as a novel class of molecular magnets, is reviewed, and a scheme of controllable synthesis of the molecular magnets at the sheared ends of carbon nanotubes is proposed.
View Article and Find Full Text PDFA Van Hove singularity (VHS) is a singularity in the phonon or electronic density of states of a crystalline solid. When the Fermi energy is close to the VHS, instabilities will occur, which can give rise to new phases of matter with desirable properties. However, the position of the VHS in the band structure cannot be changed in most materials.
View Article and Find Full Text PDFEngineering the morphology and structure of low-dimensional carbon nanomaterials is important to study their mechanical and electrical properties and even superconductivity. Herein, first the techniques that are used to engineer carbon nanotubes, including manipulation, morphology modification, and fabrication of complex nanostructures, are reviewed. This is followed by a summary of the methods applied to fabricate graphene nanostructures, such as heterostructures and nanoenvelopes of graphene.
View Article and Find Full Text PDFAdv Sci (Weinh)
February 2018
Nanogap engineering of low-dimensional nanomaterials has received considerable interest in a variety of fields, ranging from molecular electronics to memories. Creating nanogaps at a certain position is of vital importance for the repeatable fabrication of the devices. Here, a rational design of nonvolatile memories based on sub-5 nm nanogaped single-walled carbon nanotubes (SWNTs) via the electromechanical motion is reported.
View Article and Find Full Text PDFWe have investigated the effect of a magnetic field on the resistance (magnetoresistance, MR) of single-walled carbon nanotube (SWNT) arrays. The SWNT devices consist of a mixture of metallic and semiconducting SWNTs between palladium electrodes. The MR of the devices is studied at room temperature and in the presence of perpendicular magnetic fields up to 0.
View Article and Find Full Text PDFIn this work, we report an effective technique of fabricating ultraclean individual suspended single-walled carbon nanotube (SWNT) transistors. The surface tension of molten silver is utilized to suspend an individual SWNT between a pair of Pd electrodes during annealing treatment. This approach avoids the usage and the residues of organic resist attached to SWNTs, resulting ultraclean SWNT devices.
View Article and Find Full Text PDFSuspended single-walled carbon nanotubes (SWNTs) have advantages in mechanical resonators and highly sensitive sensors. Large-scale fabrication of suspended SWNTs array devices and uniformity among SWNTs devices remain a great challenge. This study demonstrates an effective, fast, and wafer-scale technique to fabricate suspended SWNT arrays, which is based on a dynamic motion of silver liquid to suspend and align the SWNTs between the prefabricated palladium electrodes in high temperature annealing treatment.
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