N-SrTiO3 nanoparticle/BiOBr nanosheet as 0D/2D heterojunctions for enhanced visible light photocatalytic dye degradation

Abstract

A novel 0D/2D heterojunction N-SrTiO3/BiOBr (NSTO/BiOBr) was constructed by uniform dispersing of N-SrTiO3 nanoparticles on BiOBr nanosheets through a facial one-step precipitation method. All the synthesized NSTO/BiOBr composite photocatalysts with different N-SrTiO3 content were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflection spectroscopy (UV–Vis DRS), photoluminescence (PL) spectra, photocurrent response, electrochemical impedance spectra (EIS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption-desorption. The visible light rhodamine B degradation results revealed that the formation of 0D/2D heterojunction NSTO/BiOBr results in improved photodegradation activity as compared with N-SrTiO3 and BiOBr, and NSTO/BiOBr with the 18% weight percentage of N-SrTiO3 is most effective among all the NSTO/BiOBr nanocomposites. The activity comparison of 18% NSTO/BiOBr with that of pure NSTO and BiOBr also conforms to their corresponding photoelectric response and electron transfer impedance measurements. Finally, RhB degradation mechanism over NSTO/BiOBr composite catalyst were proposed.