Thin layer of ordered boron-doped TiO2 nanotubes fabricated in a novel type of electrolyte and characterized by remarkably improved photoactivity

• DOI: 10.1016/j.apsusc.2015.09.130
• Publication Date: 2015-09-16T13:32:44Z
• Authors: Katarzyna Siuzdak; Mariusz Szkoda; Anna Lisowska-Ole...; Katarzyna Grochowska; Jakub Karczewski; Jacek Ryl
• Keywords: Photocurrent; Anodizing

Abstract This paper reports a novel method of boron doped titania nanotube arrays preparation by electrochemical anodization in electrolyte containing boron precursor – boron trifluoride diethyl etherate (BF 3 C 4 H 10 O), simultaneously acting as an anodizing agent. A pure, ordered TiO 2 nanotubes array, as a reference sample, was also prepared in solution containing a standard etching compound: ammonium fluoride. The doped and pure titania were characterized by scanning electron microscopy, UV–vis spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, photoluminescence emission spectroscopy and by means of electrochemical methods. The B-doping decidedly shifts the absorption edge of TiO 2 nanotubes towards the visible light region and significantly inhibits the radiative recombination processes. Despite the fact that the doped sample is characterized by 4.6 lower real surface area when compared to pure titania, it leads to the decomposition of methylene blue in 93%, that is over 2.3 times higher than the degradation efficiency exhibited by the undoped material. The formation rate of hydroxyl radicals ( OH) upon illumination significantly favours boron doped titania as a photocatalytic material. Moreover, the simple doping of TiO 2 nanotubes array results in the enhancement of generated photocurrent from 120 μA/cm 2 to 350 μA/cm 2 registered for undoped and doped electrode, respectively.