W2C–SiC nanocomposite fibers were fabricated by electrospinning and pyrolysis using tungsten nanoparticle (nW; diameter, 3-5 nm) dispersed polycarbosilane solution. The nW was uniformly dispersed in the electrospun polycarbosilane fibers and transformed into α-W2C during pyrolysis at 1200 oC, where the polycarbosilane-derived SiC fibers acted as a source of carbon and as an effective support for the α-W2C nanoparticles, preventing them from converting into another phase at 1200 oC. A part of the nW dispersed on the fiber surface is considered to transform into α-W2C at the early stages of pyrolysis by carburization with the gases evolved during the pyrolytic decomposition of poly carbosilane, such as CH4.
Keywords: Tungsten carbide (W2C), Catalyst, Tungsten nanopowder (nW), Electrospinning, Polycarbosilane, SiC fiber, Catalytic support materials (CSMs).