Effects of TiO2 surface fluorination on photocatalytic degradation of methylene blue and humic acid

摘要: Photocatalytic degradation (PCD) reactions of cationic methylene blue (MB) and anionic humic acid (HA) were studied in naked TiO2 fluorinated (F-TiO2) suspensions order to investigate how the modification surface functional group influenced PCD reactions. Adsorption behaviors MB HA followed a typical pH-dependent electrostatic interaction mechanism. On other hand, those F-TiO2 markedly changed even showed reversed dependence specific pH ranges due fluoride interrupting substrates titanol groups. rates (k MB) its N-demethylation (Δλ max) significantly increased by fluorination below circum-neutral range, particular, factor 12 54 at 2, respectively. In case HA, had an insignificant effect on rate but appeared change behavior. It has been suggested that, although primary enhances photocatalytic production hydroxyl radicals, with could affect as well.