  Inorganic oxyfluorides have significant importance in the development of new
functionalities for energy production and storage, photonics, catalysis, etc.
In order to explore a simple preparation route that avoids the use of toxic HF
or F2 gas as a reaction reagent, we have employed polytetrafluoroethylene
(PTFE). Five oxyfluorides including Nb5O12F, Nb3O7F, Ta3O7F, TaO2F, and
Mo4O11.2F0.8 were synthesized by reactions between PTFE and transition metal
oxides in sealed quartz ampules. The reaction mechanism was studied by means of
gas analysis, which detected SiF4 as a main product gas during the reaction. A
possible reaction mechanism between the PTFE and transition metal oxides is
discussed.
