Ultrasound and microwave technology for flake-TiO2 growth and immobilization on cotton fabrics in micro-dissolution process

Recent years have witnessed the explosive progress of functional nano materials in textile field, requires us to re-recognize and understand the potential hazards of nanoparticles. A harmless, cost-effective and facile approach of growing functional particles with special morphology and immobilizing onto cellulose fabric (CF) to prepare functional fabrics is highly desired. Here, commercial TiO2 nanoparticles (TiO2 NPs) grow under ultrasound-microwave and form a flake-like structure, which retain excellent photocatalytic degradation ability and prevented the potential harm to human body when nanoparticles fell off. The method was implemented based on 4-methylmorpholine-N-oxide (NMMO) aqueous system which was approved as a favorable solvent for dissolving cellulose, and grew flake-TiO2 on cotton fibers under the assistance of the ultrasound and microwave. The as-prepared TiO2-CF possessed satisfactory photocatalytic activity for Methylene blue (MB) and Rhodamine B (RhB) dyes under ultraviolet light with the low dye residue rate of about 5% and 1%, respectively. After 50 times rigorous washing procedures, the titania loading next to 18% was confirmed by thermogravimetric analysis, which proved that TiO2-CF had good wash fastness.