It has been demonstrated that one-dimensional carbide materials could be synthesized using multi-wall carbon nanotubes as templates by reaction with volatile oxide and/or halide species.[1,2] It is reasonable to expect that the nanofibers may also be used as templates to produce carbide nanowires by high temperature reactions. Electrospinning has received a steadily increasing interest due to its ability to produce nanometer-sized fibers with a high level of alignment.[3-8] A large number of polymers have been electrospun into nanofibers with a typical range of fiber diameters from 50 run to 500 run. Single-wall~[3] and multi-wall carbon nanotubes~[5,6] were successfully embedded into polymer to form nano-composite fibers by electrospinning, leading to improvement in mechanical properties. Ceramic fibers~[4] were also produced by electrospinning by the use of a mixture of ceramic precursors with a polymer as spinning dope. The electrospun composite fibers were then calcined in air to burn out the polymer matrix, resulting in the formation of polycrystalline ceramic nanofibers. However, single crystal nanowires that have better mechanical and electrical properties could not be produced by direct electrospinning. Here we report the structure and composition of SiC nanowires synthesized using electrospun polyacrylonitrile (PAN) nanofibers as a template. The advantage of this process is that single crystalline nanowires can be obtained in a relatively large quantity. Compared with SiC whiskers or nanowires synthesized by vapor-liquid-solid (VLS) mechanism,[9-11] SiC nanowires produced in our process have a uniform cross section, well-ordered structure, very low concentration of stacking faults and contain no catalyst.
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