Abstract
Bismuth oxybromide samples were synthesized using solvothermal crystallization and different additives (CTAB-cetyltrimethylammonium bromide, PVP–polyvinylpyrrolidone, SDS–sodium dodecyl sulfate, U–urea and TU–thiourea). The effect of the mentioned compounds was investigated through structural (crystallite size, crystal phase composition, etc.), morphological (crystal shape), optical (band gap energy) parameters, surface properties (surface oxidation states), and the resulting photocatalytic activity. It was found that the ratio of the (1 0 2)/(1 1 0) crystallographic planes, the presence of oxidized Bi4+ and Bi5+ species were responsible for the obtained photocatalytic activity. Moreover, a strong dependency was revealed between the surface tension of the shape tailoring agents and the overall morpho-structural parameters, pointing out the fact that the properties of the semiconductor can be more easily tuned using the surface tension modification as a tool.
Highlights
Bismuth based photocatalysts are a new generation of semiconductor materials, which can have promising photocatalytic applicability
For the synthesis 2.36 g Bi (NO3)3·5H2O (VWR, 98.0%) was dissolved in of 50 mL ethylene glycol (VWR Chemicals, 99.5%), and 0.2 g of shape-tailoring agent such as polyvinylpyrrolidone (PVP K30 abbreviated as PVP) (Molar Chemicals 99%), sodium dodecyl sulfate (SDS) (Biolab 98%), cetyl trimethylammonium bromide (CTAB) (Sigma Aldrich, 98%), urea (U) (Molar Chemicals 99%) or thiourea (TU) (Sigma Aldrich, 99%) was added to the solution
The results suggested that the synthesis of BiOBr in the presence of surfactants showed increased primary crystallite size values compared to the reference sample (e.g.: BiOBr_∅ 12 nm vs. BiOBr_TU 25.3 nm) except for BiOBr_SDS which showed 11.5 nm-sized crystallites
Summary
Bismuth based photocatalysts are a new generation of semiconductor materials, which can have promising photocatalytic applicability. Bismuth oxyhalides have been intensively examined, due to their unique layered structure and narrow band gap, they can have increased photocatalytic efficiency [7]. Their structure is composed of [Bi2O2]2+ sheets and enclosed double-layered halogen anions can be found bonded through van der Waals interactions. Among the BiOX materials, BiOBr has advantageous properties, like narrow bad gap, chemically stable or the aforementioned unique crystal structure, which makes BiOBr a suitable photocatalyst [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
