The effect of polyvinylpyrrolidone (PVP) on the growth of (1 1 0) crystal facet of BiOCl for enhanced photodegradation of RhB under LED

Controlling the morphology and directions of crystal facets is one of the effective factors on the photocatalytic performance of bismuth oxyhalides. In this paper, the effect of the presence of PVP polymer as a structure directing agent for the growth of BiOCl crystal facets made by a simple co-precipitation method has been investigated. The results showed that the prepared PVP-BiOCl samples display much more photocatalytic activity in comparison to pure BiOCl. So that in the presence of BiOCl-P0.5 sample more than 95 % of RhB molecules are degraded in 30 min under the LED lamp. This is while, this number for the pure BiOCl sample is about 62 %. Characterization of nanoparticles was performed by different methods such as XRD, FTIR, TGA, FESEM, EDS and DRS. That according to the results, the improvement of the photocatalytic activity of BiOCl-P0.5 compared to pure BiOCl is attributed to the activation of the nanoparticle surface with hydrophilic PVP molecules, as well as the effect of this polymer as a structure directing agent on the morphology and changing the direction of the dominant crystal facets from (1 0 0) to (1 1 0). Finally, with the aid of experimental data and trapping active species the degradation mechanism of RhB molecules was provided.