Studies of the Surface of Fluorinated Carbon in the Aspect of its Catalytic Properties

Surface properties of fluorinated carbon were characterised from the point of view of its use as a material for catalytic purposes. Samples with different fluorine content (from 10 to 65 wt.% ) were tested for their catalytic activity for a number of reactions of acid-base catalysis involving residual hydroxyl groups as active centres. It was found that they were capable of catalysing only such a reaction proceeding through the formation of carbenium ion for which the presence of very weak acid centres is sufficient. The generation of only weak acidity as a result of fluorination was unexpected, therefore calculations were performed using AM1 method to explain this fact. A simple molecule used as a model of fluorinated carbon surface enabled to predict acidity of residual OH groups which was in agreement with experimental findings.