Zinc oxide (ZnO) is an inorganic compound, which in addition to photocatalytic, semi-conductive and antibacterial properties, provides excellent protection against ultraviolet (UV) radiation. Textiles that offer UV protection play an important role in prevention of skin damages caused by UV radiation. The aim of master's thesis research, was to investigate different parameters of in-situ synthesis of ZnO nanoparticles (ZnO-NP) on cotton in order to achieve high UV protecton factor (UPF). In the first part of the research the influence of different reducing agents (Na2CO3, KOH, NaOH) and it's molar concentration (0,1M and 1M) on formation of nanoparticles and UPF values of cotton fabric was studied. The second part of the research was focused on other parameters of in-situ synthesis, such as treatment time in ZnCl2 precursor, synthesis time (time of treatment after adding the reducing agent) and drying time after in-situ synthesis. Using UV/Vis spectroscopy high UPF values were determined on cotton fabric, where in-situ synthesis was performed using NaOH and KOH, both in 1M molar concentration. The use of NaOH resulted in higher UPF value of cotton fabric. The content of ZnO particles was examined with inductively coupled plasma mass spectrometry (ICP-MS). As expected, the results showed higher content of zinc on the fabric, where NaOH was used for in-situ synthesis. Scanning electron microscopy (SEM) showed that use of this reducing agent resulted in cotton fabric, completely covered with small, round shaped nanoparticles. From the second part of the research it was discovered that synthesis time has the biggest influence on UPF value of cotton fabric. Treatment time in precursor did not importantly affect the UV protection of the fabric. Besides that, longer drying time did not result in higher UPF value, although it had a big influence on morphology of the synthesized nanoparticles. With longer drying time the nanoparticles were more round shaped. The samples had poor wash fastness even after the first wash, which was observed by removal of the majority of ZnO nanoparticles.
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