Abstract: Single-walled carbon nanotubes (SWNTs) with enriched (n, m) species are in high demand for various advanced applications. Since the SWNT structure is largely influenced by the chemistry of the active catalyst during growth process, exploiting novel catalyst with bias towards specific SWNT chiralities has been challenging. In this work, we introduce a vanadium catalyst supported by mesoporous magnesia (V-MgO) for the selective growth of SWNTs using CO chemical vapor deposition (CVD). At a reaction temperature of 650 °C, the (6, 5) SWNT content reaches an impressive 67.9 % among all semiconducting species, exceeding the selectivity of many commercial SWNT products. Post-CVD analysis reveals that the catalyst transforms into vanadium carbide (VC), which acts as a nucleation site for SWNT growth. Molecular dynamics simulations indicate that the energy at the SWNT-VC interface and the growth kinetics of SWNTs contribute to the chirality selectivity. This research opens up possibilities for the selective synthesis of SWNTs using cost-effective early transition metals, illuminating their future applications in fields such as bioimaging.

Key words: Single-walled carbon nanotubes, Chirality selective growth, (6,5) tubes, Supported vanadium catalyst, Molecular dynamics simulations