EFFECT OF ANNEALING TEMPERATURES ON THE CRYSTALLIZATION AND PHOTOCATALYTIC ACTIVITY OF MICRO-NANOPOROUS TiO2 FILMS PRODUCED BY ELECTROCHEMICAL ANODIZATION

Yıl 2018, Cilt: 5 Sayı: 1, 85 - 92, 15.12.2017

Melis Yurddaskal Metin Yurddaskal Tuncay Dikici Hülya Durmuş

https://doi.org/10.18596/jotcsa.370781

Öz

In this study, micro-nanoporous
TiO₂ films were prepared by electrochemical anodization of titanium
(Gr-2) in an aqueous solution containing 0.5 wt. % HF solution at a constant
potential of 30 V and then annealed in ambient air at 500, 600, 700 and 800 °C for 2 h to obtain crystalline
structures. The crystalline phase and surface morphology of the samples were
characterized by X-ray diffraction (XRD) and scanning electron microscope
(SEM). The photocatalytic performances of the samples were evaluated by the
photocatalytic degradation of aqueous methylene blue (MB) solutions under UV
light illumination for different periods. XRD results indicated that at
annealing temperatures higher than 600°C, anatase started to transform into
rutile. Increasing annealing temperatures resulted in reduced micro-nanopores
diameter and increased wall thickness. At 800°C, the structure completely
disappeared. The results demonstrated
that changes in both the
crystalline structure and surface morphology have a strong influence on the
photoactivity of the nanostructured TiO₂
films.

Anahtar Kelimeler

Nanostructured TiO2, anatase, surface morphology, photocatalytic, methylene blue

Kaynakça

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