Effects of silica coating on photocatalytic reactions of anatase titanium dioxide studied by quantitative detection of reactive oxygen species

Mechanism of the OH Radical Generation in Photocatalysis with TiO2 of Different Crystalline Types

“…The Ti-peroxo is produced from two trapped holes and equivalent to the adsorbed H 2 O 2 . 27 Therefore, this mechanism On the other hand, for anatase TiO 2 , the • OH generation could not be explained by this reaction mechanism, because the addition of H 2 O 2 decreased the • OH generation, as shown in Figure 6 for ST-01 TiO 2 and in our previous studies for ST-01, 28 ST-21, and AMT-600 TiO 2 . 12 In the previous research, 12 the amount of • O 2 − , which is formed by the oxidation of H 2 O 2 or the reduction of O 2 , was measured for several kinds of TiO 2 powders.…”

Silica modification of titania nanoparticles enhances photocatalytic production of reactive oxygen species without increasing toxicity potential in vitro

“…This behaviour could be ascribed to the potential ability of silica to prevent the radical recombination through the formation of hydrogen peroxide molecules, as elsewhere reported. 44 Photoabsorption in TiO 2 produces, in fact, conduction band electrons (e À ) and valence band holes (h + ) (eqn (1)). The quantity of H 2 O 2 produced by the chain reactions comes from both the reduction of the oxygen molecules by the conduction band electrons (eqn (2) and 3) and by water oxidation by the valence band holes (eqn (4) and (5)).…”

Role of active oxygen species in the liquid-phase photocatalytic degradation of RhB using BiVO 4 /TiO 2 heterostructure under visible light irradiation

“…It depends on where the initial excitation occurs, which directly affects whether the reaction product comes from a photocatalysis process or a photosensitization process. Moreover, in the photocatalytic process, the active oxygen species are of remarkable importance because they are key species to initiate the reactions [3,[24][25][26]. It is crucial to figure out some points concerning these active species include their sources, their reactions pathways, and their ability to react with dye pollutants to produce non-toxic small molecules that are easily biodegradable in the aquatic environment.…”