Large-scale synthesis of hafnium carbide nanowires via a Ni-assisted polymer infiltration and pyrolysis

Hafnium carbide (HfC) nanowires were successfully synthesized on C/C composites via a Ni-assisted polymer infiltration and pyrolysis. Before synthesizing HfC nanowires, the composition and microstructure of the organic HfC precursor and its pyrolyzed products were characterized by Fourier transform infrared spectra, X-ray photoelectron spectroscopy, and X-ray diffraction. The effect of heat-treatment temperature on the morphology and microstructure of HfC nanowires were investigated by scanning electron microscopy and transmission electron microscopy. Results show that HfC nanowires exhibits three-layer core-shell structure, including HfC core, HfO ₂ inner shell (~2 nm) and carbon nanosheet outer shell (~1 nm). The obtained HfC nanowire is typically grown along <01 (Formula presented.) > with the diameters of ~100 nm and the length of several micrometers. The growth of HfC nanowire follows the combination of top-type vapor-liquid-solid and solid-liquid-solid mechanism.