Thermolysis of Fluorinated Single-Walled Carbon Nanotubes: Identification of Gaseous Decomposition Products by Matrix Isolation Infrared Spectroscopy

摘要

The thermal decomposition of fluorinated single-walled carbon nanotubes (F-SWNTs),known to result in pristine SWNTs,has been investigated by freezing the gaseous products formed at temperatures between 50 and 500 deg C under high vacuum in an argon matrix at 10-20 K and analyzing the trapped species by IR Spectroscopy. The major products of F-SWNT decomposition are carbonyl fluoride (COF_2) below 300 deg C and CF_4 above 300 deg C. For comparison,graphite fluoride is stable thermally up to 300 deg C under these conditions,and the major gas-phase species at temperatures below 500 deg C are CF_4 and the CF_3 radical. F-SWNTs are thermally less stable than graphite fluoride,and etching of the nanotubes is observed at lower thermolysis temperatures.