Oxidation reactions reduction mechanisms, basic principles

However, due to the inherent complexity of this minute photoelectro-chemical system, details of the underlying reaction mechanisms of photocatalysis are even today still far from being understood. In contrast to an ordinary photoelectrochemical cell which employs an external bias voltage to deliberately separate oxidation and reduction processes in different compartments of the reactor, in photocatalysis both processes occur on the surface of the same semiconductor particle, usually only separated by a distance of a few angstroms. Moreover, as is evident from basic principles, the reaction rate of the overall process will be limited by the... 

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