Dip-coating deposition of BiVO^sub 4^/NiO p-n heterojunction thin film and efficiency for methylene blue degradation

• Published in: Journal of materials science. Materials in electronics 2015-10, Vol.26 (10), p.7705
• Main Authors: Da Silva, M R, Scalvi, L V, A, Neto, Vanildo Souza, Leão, Dall'antonia, L H
• Format: Article
• Language: English
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-015-3412-6

This paper deals with a simple FTO/p-n heterojunction electrode assembly formed by BiVO^sub 4^ and NiO thin films, where the precursor solution is obtained by solution combustion synthesis and precipitation in aqueous media techniques, respectively, whereas the thin films were deposited by the dip-coating deposition process. The FTO/p-n electrodes are characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy and UV-Vis spectroscopy. The performance analysis based on the methylene blue degradation reaction have shown that the p-n electrodes, FTO/p-NiO/n-BiVO^sub 4^ and FTO/n-BiVO^sub 4^/p-NiO have higher electroactivity under visible light irradiation condition when compared to single BiVO^sub 4^ thin film, deposited separately, with estimated k ^sub obs^ value of 340 × 10^sup -4^ min^sup -1^, 270 × 10^sup -4^ min^sup -1^ and 150 × 10^sup -4^ min^sup -1^, respectively.