Abstract:
Titanium dioxide photocatalysts co-doped with iron(III) and lanthanum(III) have been prepared
through a modified sol–gel method. Doping with Fe
3 þ
resulted in a relatively lower anatase to rutile
phase transformation temperature, while La
3 þ
addition reduced the crystal growth and thus retarded
the phase transformation of titania nanoparticles. The presence of Fe
3 þ
ions shifted the absorption
profile of titania to the longer wavelength side of the spectrum and enhanced the visible light activity.
On the other hand, La
3 þ
addition improved the optical absorption of titania nanoparticles. Both the
dopants improved the life time of excitons by proper transferring and trapping of photoexcited charges.
In the present work, considerable enhancement in photocatalytic activity under visible light was
achieved through synergistic effect of optimum concentrations of the two dopants and associated
crystal defects.
