SiC nano-wire and preparing method thereof

Abstract

Disclosed are a SiC nanowire and the preparation method which relates to nanowires and preparation methods and solves the problems that the existing SiC nanowire is of complex preparation technology, difficult control, high cost and environmental pollution. The SiC nanowire of the invention adopts industrial silicon powder and graphite powder and is made through atmosphere sintering from the mixture of 50 to 75 percent of industrial silicon powder and 25 to 50 percent of graphite powder according to the mass percentage. The preparation method of the invention is that, first, industrial silicon powder and graphite powder are evenly mixed are put into a graphite crucible; second, the graphite crucible is placed into an atmosphere sintering furnace for vacuum pumping; third, argon gas in pumped into the atmosphere sintering furnace; fourth, the graphite crucible and the argon gas are sintering in the atmosphere sintering furnace with the furnace cooling to room temperature in order to produce SiC fibers. Industrial silicon powder and graphite powder are selected in the invention as raw materials, so that the cost is reduced while the technology is simple and easy to operate. No environmental pollution is caused in the process of the reaction. The product is single-crystal phase beta -SiC fibers with uniform thickness, wherein, the diameter is mainly between 30 to 150 nanometers, the length is controllable, and the longest can reach mm-magnitude.

Description

technical field [0001] The invention relates to a method for preparing nanofibers. Background technique [0002] In 1995, Dai and others from the Department of Chemistry of Harvard University successfully synthesized SiC nanowires for the first time using carbon nanotubes as templates, that is, SiC fibers with nanometer dimensions, which opened up a new era in the field of SiC fiber research. The results were published in the world's top academic In the journal NATURE (NATURE.VOL375, 29 JUNE1995). Compared with large-size SiC fibers, nano-SiC fibers have fewer internal defects, a more perfect crystal structure, higher mechanical properties, and elastic modulus and tensile strength close to theoretical values. Eric W.Wong et al. published their research results on SCIENCE (Science 277, 1971 (1997)), showing that the flexural strength of SiC fibers can be as high as 53.4GPa, which is 2 to 4 times that of carbon nanotubes, much higher than that of carbon nanotubes. Ordinary f...

AI Technical Summary

Problems solved by technology

[0003] The present invention provides a SiC nanowire and its preparation method in order to solve the problems of complex process, difficult control, high cost and environmental pollution in the existing SiC nanowire preparation method. The specific technical solution for solving the above problems is as follows: