Reduction of hazardous reactive oxygen species (ROS) production of ZnO through Mn inclusion for possible UV-radiation shielding application

Abstract

Mn x -ZnO (1-x) nanopowders were successfully synthesised through a simple sol-gel method. The samples were annealed at 300 C to enhance their crystallinity. The lattice structure, morphology and optical properties of the prepared powdered samples were extensively studied using different characterization techniques, confirming the formation of Mn x -ZnO (1-x) . The inclusion of Mn did not cause any change to the wurtzite structure of ZnO; however slight peak shifting and increase in lattice parameters were indicated. The normal absorption spectra pointed to a cut-off edge extending beyond the UV region and a Burstein-Moss type band gap broadening induced by the Mn doping. ZnO showed excellent photodegradation activity against methylene blue (MB) upon UV irradiation. Intensifying the dopant concentration resulted in further diminution of photoactivity against MB. This reduction of photocatalytic activity of ZnO upon doping can be drawn to be due to the presence of Mn in the ZnO lattice, which acted as recombination sites for the photogenerated charge carriers.The results demonstrated that doping ZnO with Mn can be used to suppress the oxidative stress induced by reactive oxygen species (ROS) through generation of recombination centres. The suppression of toxic ROS generation implies possible application in fabrics and ointments for UV shielding applications.

Enhanced photocatalytic performance of ZnO/AgCl composites prepared by high-energy mechanical ball milling

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UV‐blocking performance and antibacterial activity of Cd, Ba co‐doped ZnO nanomaterials prepared by a facile wet chemical method

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Methylotroph bacteria and cellular metabolite carotenoid alleviate ultraviolet radiation-driven abiotic stress in plants

“…Solar ultraviolet (UV) radiation on the earth's surface is increasing due to stratospheric ozone depletion, caused by an accelerated increase in greenhouse gas emission. Solar UV radiation is mainly three types: UV-A radiation (315-400 nm) leads to indirect damage to cellular DNA, proteins, and lipids by generating intracellular reactive oxygen species (Sage et al, 2012;Lefatshe et al, 2020). UV-B (280-315 nm) radiation causes direct DNA damage by inducing the generation of DNA photoproducts, such as pyrimidine dimers (Acuña-Rodríguez et al, 2021).…”