Effect of post-synthesis acid activation of TiO2 nanofilms on the photocatalytic efficiency under visible light

18th International School on Condensed Matter Physics: "Challenges of Nanoscale Science: Theory, Materials, Applications"

Stambolova, I.^1 ; Blaskov, V.^1 ; Shipochka, M.^1 ; Eliyas, A.^2 ; Vassilev, S.^3

Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev St. bl. 11, Sofia

1113, Bulgaria^1

Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St. bl. 11, Sofia

1113, Bulgaria^2

Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. G. Bonchev St. bl. 10, Sofia

1113, Bulgaria^3

关键词: Degradation rate constants;    Dye photodegradation;    Hydroxyl content;    Instrumental methods;    Photo catalytic degradation;    Photocatalytic activities;    Photocatalytic efficiency;    Surface characterization;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/558/1/012055/pdf
DOI  :  10.1088/1742-6596/558/1/012055

来源: IOP

【 摘 要 】

Nanosized TiO2films were deposited by spray pyrolysis and thermally treated at 400oC. Then the films were dipped in 1M aqueous solution of HCl. The activated samples were divided into two parts - one part was dried (A) and another was annealed (AT) in air. The photocatalytic degradation of Reactive Black (RB5) textile dye under visible light was tested. The following instrumental methods: X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were applied for the phase and surface characterization of obtained samples. According to Raman and XRD analyses all films are anatase. The XRD showed that activated films are better crystallized than non activated TiO2film. The presence of chlorine at 200.3 eV was registered for acid activated samples by X-Ray photoelectron spectroscopy. The acidic activated films exhibited higher rate of dye photodegradation than that of the reference TiO2sample. The photocatalytic efficiency decreases in the order A > AT> non activated TiO2films. The degradation rate constant for acid activated films is two times higher than those of the reference film. The hydroxyl content in TiO2acidic activated films is greater than that of the non- activated films, which results in significant increase in the photocatalytic activity. In addition, the presence of chlorine may also lead to enhancement in efficiency.