Thickness-tunable solvothermal synthesis of BiOCl nanosheets and their photosensitization catalytic performance

Bismuth oxychloride (BiOCl) nanosheets with tunable thickness were synthesized via a facile solvothermal method. The obtained BiOCl products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. It was found that the metal ions (Fe3+, Co2+ and Na+) played a significant role in modulating the thickness of two-dimensional (2D) BiOCl nanostructures. Compared with commercial P25 and commercial BiOCl, the as-prepared BiOCl nanosheets exhibited superior activity for photosensitization degradation of organic dyes upon visible light irradiation. Furthermore, the photosensitization degradation activities were strongly correlated with the thickness of BiOCl nanosheets. The thinner nanosheets demonstrated a relatively high activity for the degradation of Rhodamine B (RhB). The enhanced photosensitization activities were ascribed to its low electron injection barrier and high electron mobility on the surface of BiOCl nanosheets, which was confirmed by transient photocurrent responses and electron impedance spectra of the samples.