Most Important Types of Photoelectrochemical Reactions

Description of the Most Important Types of Photoelectrochemical Reactions 

Let us now turn, using the concept of quasi-Fermi levels, to the description of qualitative peculiarities in the occurrence of photo-electrochemical reactions at an illuminated semiconductor/electrolyte interface. 

The quasithermodynamic approach employed below relies upon the assumption that an electrode reaction is accelerated under illumination due to the formation of quasi-levels F and Fp, which are shifted relative to the equilibrium position F. Conditions (16a) and (16b) should now be modified. Namely, for an anodic process to occur with holes being involved, the following inequality should 

FhvhsO- (Wc consider the case where semiconductor decomposition with involvement of holes, and water-to-hydrogen reduction, with involvement of conduction-band electrons, are the most probable anodic and cathodic reactions, respectively). 

Let us consider the effects related to the formation of quasi-Fermi levels of electrons and holes. For majority carriers (electrons), the shift of F with respect to F is very small, as was noted above, and it is usually neglected on the contrary, for minority carriers 

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