Ultrasound assisted surface micro-dissolution to embed nano TiO₂ on cotton fabrics in ZnCl₂ aqueous solution

In this paper, a simple and environment friendly approach was used to prepare the multifunctional composite fabrics via coating commercial TiO₂ nanoparticles (NPs) on the surface of cotton fibers by surface micro-dissolution process in 55%wt ZnCl₂ aqueous solution under the aid of ultrasound without any adhesive. The TiO₂/cotton composite fabrics were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and thermal gravity (TG) methods. The treated fabric had photocatalytic property in Rhodamine B (RhB) degradation, and had good antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) cultures. The results of contamination degradation and antibacterial experiments confirmed that ultrasonic vibration had a significant effect on the tightly coating of nanoparticles on cotton fiber surface in the process of micro-dissolution. Even after intense ultrasonic washing, the contamination degradation rate and antibacterial efficiency of S3 (with ultrasonic) still reach 95% and 99% respectively, while S4 (without ultrasonic) only remained 72% and 59% of S2, which was attributed that ultrasonic facilitated the entry and load of nanoparticles onto the fabrics. The mechanical property of treated cotton fabrics kept well.