Greatly Enhanced Photocatalytic Hydrogen Peroxide Production over Titanium Dioxide using Anthraquinone-based Co-Catalysts

In this study, anthraquinone derivatives were explored as cocatalysts on titanium dioxide nanoparticles (P25) for the photocatalytic production of hydrogen peroxide from oxygen. The screening of anthraquinone derivatives revealed that 1-hydroxyanthraquinone is the most effective cocatalyst on P25 and increases the reaction rate greatly, by a factor of 30. In addition, the impact of various reaction parameters on the kinetics of hydrogen peroxide formation such as light intensity, wavelength, the amount of cocatalyst on P25, oxygen flux and the pH value, were investigated. Using this data allowed optimization of the reaction with respect to high reaction rate (1.9 mM min -1 ), quantum yield (26.7%) or turnover number of the AQ co-catalyst (2300). In particular, the extremely high formation rate represents a new benchmark for this reaction.