Case Studies on Heterogeneous Photoredox Reactions

As seen in Fig. 10.9 the rate reaches a plateau, consistent with the assumption that the rate is directly proportional to the surface concentration of 4-CP. 

In these photocatalytic oxidation processes the organic compound is either directly oxidized by the valence band holes  

The photoelectrons of the cb react with adsorbed molecular oxygen, eventually leading to formation of H202. 

Effect of 4-chlorophenol (4-CP) concentration on the rate of degradation of 4-CP ( ) and the rate of formation of hydroquinone (O), which is a major intermediate of the 4-CP degradation. Conditions initial pH 5.8 flow rate, 250 ml min 1 temperature, 30 2° C. 

H202 (and organic peroxides) can be formed by either the reduction of 02 by e, b or the oxidation of H20 by h+b as follows (Hoffmann, 1990)  

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