Metal–Organic Framework as Catalyst Precursor of Floating Catalyst Chemical Vapor Deposition for Single-Walled Carbon Nanotube Manufacture

The floating catalyst chemical vapor deposition (FCCVD) method is one of the most important technologies for the mass manufacture of single-walled carbon nanotubes (SWCNTs). In this paper, we first attempt to use metal–organic frameworks (MOF) as the catalyst precursor of FCCVD and successfully obtain high-quality SWCNTs without gaseous carbon sources. The preparation experiment was conducted by injection of the ZIF-67 dispersion in ethanol solution into a tubular furnace at 1100 °C under H2 atmosphere. ZIF-67, ethanol, and H2 acted as the catalyst precursor, carbon source, and carrier gas, respectively. The presence of H2 around the ZIF-67 prevents the Co nanocatalysts from quick aggregation, and ethanol significantly accelerates ZIF-67 decomposition and SWCNTs formation during FCCVD. The as-prepared SWCNTs feature a narrow diameter distribution and high purity and demonstrate promise for building multiple macrostructures and the application of an antibacterial field as an efficient photocatalyst. Compared with the traditional catalyst precursor of ferrocene, ZIF-67 is cheap and nontoxic. Moreover, the gaseous carbon sources are replaced by ethanol, which greatly decreases the manufacture cost and harm to environments. Our investigation displayed the great potential of MOF in FCCVD, offering an efficient and low-cost method to manufacture SWCNTs.