Enhanced visible light photocatalytic degradation of organic pollutants by iron doped titania nanotubes synthesized via facile one-pot hydrothermal

Abstract

The photoactivity of iron doped titania nanotubes (Fe-TNT) synthesized via facile hydrothermal technique was investigated using reactive black 5 (RB 5) as the model pollutant. The incorporation of iron (Fe) nanoparticles in titania nanotubes (TNT) structure was confirmed via x-ray diffraction while x-ray photoelectron spectroscopy analysis showed the presence of Fe3+ ions in the nanotube structure. Ultraviolet-visible spectrophotometer analysis confirmed the reduction in band gap energy, from 3.595 eV to 2.097 eV due to the interaction between Fe into TNT structure. The formation of tubular structure has also increased the specific surface area of the photocatalyst from 56.00 m2/g to between 246.23 m2/g to 142.01 m2/g for all Fe-TNT. Fe-TNT with Fe:Ti ratio of 1:3 demonstrated promising photodegradation efficiency of 90% within 120 min of visible light irradiation. The reduced band gap energy and improved visible light responsiveness imparted by incorporation of Fe nanoparticles into structure of TNT are the main factors for improved photocatalytic degradation.