In situ reduction of TiO2 nanoparticles on cotton fabrics through polydopamine templates for photocatalysis and UV protection

In this work, titanium dioxide (TiO₂) nanoparticles were immobilized on the surface of cotton fabrics by in situ reduction on polydopamine (PDA) templates. Evidenced by the results of scanning electron microscopy/energy-dispersive X-ray analysis (SEM–EDX), Fourier transform infrared and X-ray photoelectron spectroscopy (XPS), PDA films were successfully formed on the surface of cotton fabrics as the templates for the in situ reduction. The morphology, chemical composition and crystal structure of the coated cotton fabrics after in situ reduction of TiO₂ nanoparticles were characterized by SEM–EDX, XPS and X-ray diffraction, respectively. These results confirmed that anatase TiO₂ nanoparticles were well-dispersed on the surface of cotton fabrics. The photocatalysis experiment results indicated that about 90% of methylene blue solution was degraded after UV illumination of the coated cotton fabrics. The thermogravimetric analysis results demonstrated that the TiO₂ nanoparticles had little effect on the thermal stability of cotton fabrics. The results of UV protection showed that the value of the ultraviolet protection factor (UPF) of the coated cotton fabrics was 127.2. The UPF value was maintained at 108.8 after five cycles of laundering, indicating excellent durability of the coating in terms of UV protection.