Fluororganic Groups Grafted on Carbon Microspheres

Fluorine-containing carbon microspheres were prepared by treatment with dichlorodifluoromethane, 1,1,1,2- tetrafluorethane and products of polytetrafluoroethylene (PTFE) pyrolysis at elevated temperature. The total fluorine content in the fluorinated carbon microspheres is extremely high it varies from 2.2 to 6.9 mmol/g. High thermal and chemical stability of microspheres fluorinated by (hydro)fluorocarbons was confirmed by thermal analysis. X- ray photoelectron spectroscopy showed that the fluorine in them is in semi-ionic form. However, specific primary cathode capacity measurements showed that 90% of fluorine is covalently bonded fluorine which is electrochemically inert. We suggest that the reported surface functionalization and fluorinated carbons can be useful in electrocatalysis for efficient oxygen transfer.