Nanotechnology in textiles has already been well explored and nanomaterials show a great potential. Especially photocatalysts, such as titanium dioxide and graphitic carbon nitride, prospering in photodegradation of organic pollutants, and metal nanoparticles, such as silver nanoparticles with antimicrobial activity, look promising. There is a lot of research concerning enhancement of textile coatings made of these nanomaterials, coating preparation simplification. It is also a question how to fabricate nontoxic coatings, harmless for the environment. In the master’s thesis, ternary nanocomposite for coating cellulose fibres, made of silver, titanium dioxide and graphitic carbon nitride, was successfully prepared. It has been shown that it exhibited great antimicrobial and photocatalytic activity. Its properties were compared to pristine cotton, fabric, coated with binary nanocomposites, and fabric, coated with single components only. Morphology analysis was obtained with x-ray diffraction and scanning electron microscope. It showed that titanium dioxide created film on fibres. On the other hand, silver and graphitic carbon nitride formed nanostructures. Spectrophotometric analysis of optical properties showed compatibility between components of coating which consequence in narrower band gap energy. That’s why less energy is needed for electron excitation in case of ternary coating, which was shown in coffee stains photodegradation experiment. Same coating made cotton fabric also more protective against ultraviolet radiation. Furthermore, coated specimens were tested for antimicrobial properties. It was shown that ternary coating gives the best protection against Gram-negative and Gram-positive bacteria and against viruses. Very good protection showed also binary coating, made of silver and titanium dioxide. Coated specimens did not show to be cytotoxic. Experiments proved that thermic and mechanic properties of coated fabric haven’t changed to such a great extent that coating would affect usable value of fabric. The formation of the heterojunction between titanium dioxide and graphitic carbon nitride, combined with the load of silver nanoparticles, enhanced photocatalytic performance of coated cellulose fibres. Concentration of coating components was high enough for antimicrobial activity, but low enough that no cytotoxic effects occurred. Cotton fabric, coated with this ternary nanocomposite was studied for the first time and has proven to be an effective sustainable solution for the textile functionalization.
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