Two birds with one stone: Simultaneous fabrication of HfC nanowires and CNTs through efficient utilization of polymer-derived ceramics

Carbon nanotubes (CNTs) are fabricated in carbon cloth by ultilizing the waste gasses when fabricating hafnium carbide nanowires (HfC_NWs) through thermal pyrolysis of Hf-containing polymer precursor. The formed HfC_NWs are distributed uniformly on the surface of the carbon fibers in carbon/carbon (C/C) composites and display perfect single crystal appearance. The pyrolysis of the Hf-containing organic precursor provides hafnium and carbon source for the growth of HfC_NWs. The released waste gasses containing CO, CH₄ and CO₂ are the main carbon source for the growth of CNTs. Specifically, the flexural strength of HfC_NWs reinforced carbon/carbon (HfC_NWs-C/C) composites is enhanced by ∼105% compared with pure C/C, and the CNTs/carbon cloth also displays improved electrochemical performance with respect to capacitor applications. The present study introduces a novel sustainable and eco-friendly process related to polymer-derived ceramics to form advanced ceramic nanocomposites and proposes a deep understanding of the growth mechanism of CNTs.