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Application of the similarity theory to analysis of photocatalytic hydrogen production and photocurrent generation

Dina V. Markovskaya, Ekaterina A. Kozlova


In this research some methods of the similarity theory were quantitatively applied to the description of the relationship between the efficiencies of the photocatalytic hydrogen production and photocurrent generation for the first time. Two possible similarity criteria, namely, such as the ratio of the number of electrons involved in the photocatalytic reaction to the generation of photocurrent ones and the ratio of energies transformed in the case of photocatalytic hydrogen evolution to the photocurrent, were obtained by the dimensional analysis. The literature data allow checking the first criterion. The application of the first possible similarity criterion to the samples with different chemical nature, solid solutions, series, in which the synthesis time or the ratio of catalyst components, electrolyte amount or its nature is changed, was analyzed. It was shown that the ratio of electrons may serve as the similarity criterion only under the conditions of geometric and physical similarities.


photocatalysis; hydrogen evolution; photocurrent generation; theory of similarity; similarity criterion; dimension theory

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