Facile preparation of Na-free anatase TiO2 film with highly photocatalytic activity on soda-lime glass

Na-free anatase TiO2 film was prepared on soda-lime glass (SL-glass) from a TiF4 aqueous solution upon addition of boric acid at 60 °C. It was found that the as-prepared TiO2 film before calcination showed a higher photocatalytic activity than the calcined sample (500 °C). This could be attributed to the fact that the calcined TiO2 film contained decent Na+ ions, which was diffused from the SL-glass substrate into the TiO2 film during calcination, resulting in the decrease of photocatalytic activity.