Ag@helical chiral TiO nanofibers for visible light photocatalytic degradation of 17α-ethinylestradiol.

Ag-modified helical chiral TiO NFs (Ag@chiral TiO NFs) were fabricated and characterized by ultraviolet-visible absorption spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. This novel material exhibited efficient photocatalytic activity for the degradation of 17α-ethinylestradiol (EE2) in water under visible light irradiation with an optimum size of deposited silver nanoparticles (Ag NPs) in the range of 12 ∼ 14 nm. The pseudo-first-order rate constant ( k) for EE2 photodegradation by Ag@chiral TiO NFs increased by up to a factor of 20.1 when compared with that of pure chiral TiO NFs. The high photocatalytic activity can be attributed to the interactions between helical chiral TiO NFs and surface plasmon resonance effect of Ag NPs. The new catalyst retains its photocatalytic activity at least up to five consecutive cycles. The results clearly demonstrate the feasibility of using Ag@chiral TiO NFs for the photocatalytic removal of EE2 and other endocrine-disrupting chemicals from water. [ABSTRACT FROM AUTHOR]