Characterization of nanoporous β-SiC fiber complex prepared by electrospinning and carbothermal reduction

The nanoporous β-silicon carbide (SiC) nano-sized fiber complex were made from precursors of various ratios with (SiO₂) as silicon source and polyacrylonitrile as carbon source by simple electrospinning method and economical carbothermal reduction. The prepared samples were characterized by SEM for surface shape, XRD for crystalline properties, TGA in air for oxygen resistance, and BET for porosity according to the precursor components (C/Si mol ratio). The samples with carbon ratio to silicon (C/Si) of five or more in the precursor showed the long fiber shape. Increasing the C/Si in the precursor solution tended to lead higher β-SiC crystalline and smaller crystallite size than low C/Si in the precursor solution because excess carbon could act as a dispersant and barrier to prevent neck growth or adhesion of SiC. The prepared samples have superior oxidation resistance as a whole. The increment of the C/Si leads to the increment of porosity. Also, it seems that the gaseous pore development of carbon during carbothermal reduction leads to mainly small pores (micro- or mesopores).