The photocatalytic properties of various nanoparticles have been intensively studied recently. Among them, plasmonic and semiconductor nanoparticles show special activity. While it has been found that the mechanism of photocatalytic activity for semiconductor nanoparticles is due to the transition of electrons from the valence band to the conduction band, such a mechanism is still unknown for plasmonic nanoparticles. The photocatalytic effect in the case of plasmonic nanoparticles is possibly associated with the emergence of zones of high electromagnetic intensity between two plasmonic nanoparticles due to the appearance of local plasmonic resonance. There is an urgent need to determine the effective frequency range of electromagnetic radiation at which photocatalytic processes occur.

In the proposed work, a device based on Arduino is developed to establish the spectral dependence of the process of organic structure photodegradation through the example of the dye methylene blue in the presence of nanosized silver under electromagnetic radiation action and to analyze the possible mechanisms of this process. The interval of light radiation frequencies that activate or inhibit the process of organic compound photodegradation is established, and probable mechanisms of interaction of organic structures with light radiation and nanosilver due to the occurrence of local plasmon resonance are also presented.