Photocatalytical properties of maze-like MoO3 microstructures prepared by anodization of Mo plate. (20th February 2017)

• Record Type: Journal Article
• Authors: Szkoda, M.; Trzciński, K.; Siuzdak, K.; Lisowska-Oleksiak, A.
• Is Part Of: Electrochimica acta. Volume 228(2017)
• Page Start: 139
• Page End: 145
• Publication Date: 2017-02-20
• Subjects: anodization -- molybdenum trioxide -- hydroxyl radicals -- photocatalytic properties; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2017.01.064
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: Method of the Mo foil anodization leads to the formation of maze-like structure of MoO3 . Anisotropic growth of α-MoO3 along the [110] direction is observed. The key role of hydroxyl radicals in photodegradation mechanism has been proved Abstract: In this work, we present a simple method of the formation of MoO3 microstructures via an electrochemical anodization of Mo plate carried out under varied conditions. The morphology, composition and structure of samples were investigated by SEM, EDX, XRD and Raman spectroscopy. The band gap energy was estimated using the Kubelka–Munk function and was found to be 2.87 eV. Finally, the photocatalytic activities of MoO3 samples were evaluated using the decolorisation of methylene blue (MB) as a model organic contamination. Additionally, photostability of the materials were verified and the formation of hydroxyl ions was investigated by photoluminescence (PL) spectra of terephthalic acid as a probe molecule. Various conditions of MB decolorization allow the main mechanism of dye decomposition to be identified. It was shown that the presence of F − during anodization positively affects photocatalytic properties of tested samples. After 2 h of constant illumination, the degradation reached 34% of the initial value of MB when α-MoO3 (prepared without F − ) was used as photocatalyst, whereas the degradation efficiency equals 57% in the case of α-MoO3 (with F − ). Furthermore, photoluminescence intensity of the 2-hydroxyterephthalic acid formed in the presence of α-MoO3 (F − ) was higher comparing to the intensity of spectra recorded in the presence of α-MoO3 .