This doctoral dissertation presents the development of a novel, environmentally friendly process for in situ synthesis of zinc oxide (ZnO) on cotton (CO) and polyester (PET) using aqueous extracts of invasive alien plants and food waste instead of classical chemical reducing agents, and aqueous extract of wood ash instead of chemical alkali. The ZnO synthesis procedure was optimised by studying different synthesis methods and parameters (type and concentration of precursor and »green« reducing agent, the order of synthesis solutions, synthesis time and temperature). Due to the different amounts of phenolic compounds (TPC) present in the »green« reducing agents, the order of the synthesis solutions (Alkali䀒Precursor-Reducing agent) proved to be a key parameter influencing the successful in situ synthesis and the uniform distribution of ZnO particles on fibres and consequently achieving the excellent ultraviolet (UV) protective properties (50+) of the CO fabric. Zinc acetate is a more suitable precursor for the in situ synthesis of ZnO than zinc nitrate, since with the latter, mechanical properties of the fabric are greatly impaired. Depending on the »green« reducing agent used, the wettability of the CO fabric can be adjusted. The reducing agents with higher TPC values enable hydrophilic properties, while the ones with lower TPC values enable hydrophobic properties of the CO. Oxygen plasma treatment was incorporated into the synthesis process on PET, first to increase the reactivity of PET to the synthesis solutions, and finally as a substitute for alkali. Plasma increased the hydrophilicity of PET and enabled an even adsorption of the reagents, resulting in uniform distribution of the in situ synthesised ZnO on the fabric. As the number of plasma treatments increased, the UV protection of fabrics also increased, due to higher ZnO content. Both alkali and oxygen plasma increase the amount of active binding sites on PET, which represent precursor nucleation sites for the formation of ZnO using »green« reducing agent. From the point of view of the most environmentally friendly in situ synthesis of ZnO, reduction of water consumption, preparation time for reagents and homogeneity of in situ synthesized ZnO on the fabric, oxygen plasma can be used instead of alkali.
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