Magnetic Field Induced Effect in the Surface Plasmon Resonance Band of Silver Nanoparticles

The ethanol solutions of the ZnO nanoparticles were placed in a constant and homogeneous magnetic field (B = 60 mT) for 5 days. These solutions were used for photocatalytic formation of ZnO/Ag nanoheterostructures under the action of UV irradiation. The production cycle was repeated during 30 days. During this time, the evolution of the obtained optical absorption spectra of solutions containing ZnO/Ag nanoparticles relative to a cuvette with pure ethanol and SEM microscopy data. Under the UV action, photocatalytic reduction of Ag (I) and the formation of a ZnO/Ag colloidal heterostructure occurs, which is characterized by an absorption maximum at 400–460 nm. It was found that within 30 days the final position of the maximum of plasmon absorption of the Ag nanoparticles, which were formed on ZnO solutions, that have been undergone magnetic field treatment, slowly shifts to the position of the latter in the reference sample. The latter circumstance indicates a “memory effect” that lasts for a month.