Study of the Photocatalytic Activity of Zinc Oxide in a Magnetic Field

Purpose of the study. Study of the influence of an external stationary magnetic field on the process of photocatalytic degradation of methylene blue in the presence of ultrafine particles of zinc oxide and under the influence of ultraviolet radiation.

Methods. Determination of the degree of photochemical degradation of the dye methylene blue by optical spectrometry using a set of spectrophotometric equipment based on SF-2000 and HR-2000 spectrophotometers. Characterization of the size distribution of photocatalytic zinc oxide particles using SmartSPM atomic force microscopy (AIST-NT), elemental composition on a JEOL 6610LV scanning electron microscope with an energy dispersive analysis attachment

(Oxford), structure and phase composition using X-ray phase analysis on an EMMA X-ray powder diffractometer (Australia).

Results. Dispersed zinc oxide particles synthesized by the sol-gel method have a size from 30 to 120 nm with an average quantitative size of 60 nm. The crystallographic structure of the photocatalyst at interplane distances corresponds to the zinc monoxide of the hexagonal syngony.   An analysis of the data on the process of photocatalytic degradation of methylene blue shows that the photoactivity of zinc oxide particles increases significantly under the action of an external stationary magnetic field. Thus, it was established that in a constant magnetic field of 0,56 Tl, the photocatalytic activity of ZnO particles increases by 20%.

Conclusion. Based on the experimental data obtained, it can be concluded that the introduction of a constant magnetic field can significantly increase the rate of photocatalytic decomposition of methylene blue. The presented results can be applied to industrial water purification from pollutants. By changing the magnitude of the magnetic field, it is possible to control the intensity of decomposition of pollutants.

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