Efficient solar-driven photocatalytic performance of BiOBr benefiting from enhanced charge separation rate

In this work, novel BiOBr photocatalyst (IL-BiOBr) with enhanced solar-driven photocatalytic activity was fabricated by a facile hydrothermal method with the assistance of ionic liquid (IL) 1-ethyl-3-methyli-midazolium nitrate ([EMIm]NO3). BiOBr and IL-BiOBr were characterized by the Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), particle size analyzer and surface photovoltage spectroscopy (SPS), respectively. The results reveal that [EMIm]NO3 increases the specific surface area, decreases the particle size, and greatly enhances separation rate of the photo-induced charge of BiOBr. The photocatalytic activity of IL-BiOBr for decolorization of rhodamine B aqueous solution was evaluated. The results illustrate that the photocatalytic performance of IL-BiOBr is more than 2.3 times of that of the reference BiOBr and the possible reason was suggested. (C) 2015 Published by Elsevier B.V.