Efficiency of cathodic arc-grown N-doped TiO 2 films for the photocatalytic reduction of Cr(VI) under UV-Vis irradiation

KLEIMAN, A; MEICHTRY, J M; XAUBET, M; GRONDONA, D; LITTER, M I; MÁRQUEZ, A

JOURNAL OF PHYSICS - D (APPLIED PHYSICS)

IOP PUBLISHING LTD

Año: 2023 vol. 56

0022-3727

The photocatalytic activity of undoped and N-doped TiO2 anatase films with differentthicknesses prepared by cathodic arc deposition on glass substrates is reported. After TiO2deposition, the doping of the films was carried out by plasma immersion ion implantation in anitrogen environment. The composition of the films was studied by x-ray photoelectronspectroscopy, the surface morphology was analyzed by atomic force microscopy and thecrystalline structure was examined by x-ray diffraction. The thickness was determined byobserving the film cross section with scanning electron microscopy. The transmittance of thefilms in the UV-Vis range was studied as well. The photocatalytic activity of the films wasevaluated through the efficiency in the reduction of Cr(VI) in the presence ofethylenediaminetetraacetic acid under UV-Vis irradiation. N-doped films presented a higherphotocatalytic efficiency than undoped films: Cr(VI) reduction after 5 h irradiation augmentedfrom 58% (pure TiO2) to 85% (N-doped TiO2) for films of 300 nm thickness, and from 69% to85% for films with a thickness of 440 nm. On the other hand, pure TiO2 films of 790 nmthickness were more efficient (99% of Cr(VI) reduction) but the effect of doping on thephotocatalytic activity was negligible.