Magnetic Orientation And Patterning Of Fullerene C₆₀ Nanofibers

In recent years, one-dimensional carbon nanomaterials are paid close attention in the field of nanoscience and technology. 1D carbon nanomaterials with special optical, electrical, magnetic, absorbing waves and field emission properties have potential applications in the field of fuel cell electrodes, catalysts, low dimensional semiconductors, and antimicrobial materials. For the applications of 1D carbon nanomaterials, patterning and orientation are key technologies, such as assembling micron and nanoelectronic devices. Generally, oriented 1D carbon nanomaterials are obtained through the methods of templates or chemical selfassembling, while the patterning are usually achieved by the way of etching and printing. All these complicated methods are failed to achieving orientation and patterning,simultaneously. So, the patterning and orientation of 1D carbon nanomaterials are becoming a newhotspot in microprocessing field.1. Magnetic orientation of fullerene nanofibers Crystalline fullerene C₆₀ nanofibers are prepared by a liquid-liquid interfacial precipitation (LLIP) method. In this paper, the fullerene C₆₀ fibers, which have high aspect ratio of length to diameter, typically a submicrometer diameter and millimeters long are briefly called fullerene C₆₀ nanofibers (FNFs). FNFs include both fullerene C₆₀ nanotubes (FNTs) with hollow structure and fullerene C₆₀ nanowhiskers (FNWs) with solid structure. Firstly, FNFs are cut in to a uniform scale by ultrasonic technology, and then a suspension is prepared by dispersing FNFs into Polyvinyl alcohol (PVA) aqueous. Finally, these well dispersed FNFs are dropped on a clean glass or silicon substrate, at the same time a magnetic field is applied parallel to the substrate. After the solvents evaporated, well oriented FNFs film are obtained perpendicular (or parallel) to the magnetic field. This method can also be widely used for other 1D organic or inorganic 1D nanomaterials.2. Magnetic patterning of fullerene nanofibersThe particles in a gradient magnetic field will be forced to move. The directions of magnetic forces acting on particles are depended on the magnetic properties of them. If the magnetic field is modulated into patterns, then the particles can be patterned due to their magnetic properties. In this paper, diamagnetic FNFs are patterned into strips by adding drops of FNFs suspension under a modulated magnetic field. The achieved pattern can be changed by changing the profiles of the modulator. In addition, simultaneous orientation and patterning of FNFs have been achieved in this paper.