Manipulating\nthe H<sub>2</sub>O<sub>2</sub> Reactivity\non Pristine Anatase TiO<sub>2</sub> with Various Surface Features\nand Implications in Oxidation Reactions

Anatase TiO<sub>2</sub> is commonly used as a catalyst/support\nin reactions involving H<sub>2</sub>O<sub>2</sub>, yet the understanding\nof interactions between common TiO<sub>2</sub> surfaces and H<sub>2</sub>O<sub>2</sub> remains limited. Herein, we synthesized well-defined\nTiO<sub>2</sub> crystallites with (101), (001), and fluorine-modified\n(001) [F-(001)] surfaces to examine how surface features, including\nthe arrangement of five-coordinated Ti (Ti<sub>5c</sub>) sites and\nthe presence of fluorine, influence H<sub>2</sub>O<sub>2</sub> activation.\nOur findings reveal that these surface features significantly affect\nthe physiochemical properties of adsorbed H<sub>2</sub>O<sub>2</sub>. Specifically, fluorine on the F-(001) surface introduces an additional\nhydrogen bond to the Ti<sub>5c</sub>-peroxo species, altering the\nelectronic structure of H<sub>2</sub>O<sub>2</sub> compared to those\nwith the (101) and (001) surfaces. Using cyclohexene as a probe substrate,\nwe successfully distinguished the reactivities of the Ti<sub>5c</sub>-peroxo species. The activity of those on the F-(001) surface was\nsignificantly higher than the activity of those on the (001) surface,\nwhile the (101) surface showed negligible oxidation activity. These\ninsights can guide the design of TiO<sub>2</sub>-based catalysts for\nH<sub>2</sub>O<sub>2</sub>-related reactions.