Synthesis of BiOI@(BiO) 2 CO 3 facet coupling heterostructures toward efficient visible-light photocatalytic properties

In this paper, BiOI@(BiO) 2 CO 3 facet coupling heterostructures were synthesized via exfoliation and ion exchange, and characterized by X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), UV-vis diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra and valence-band XPS spectra. With the reaction time increasing, more BiOI can be transformed to (BiO) 2 CO 3 , and BiOI@(BiO) 2 CO 3 facet coupling heterostructures were obtained. The photocatalytic results showed that BiOI@(BiO) 2 CO 3 displays much higher photocatalytic activity than BiOI and (BiO) 2 CO 3 under visible-light. The photocatalytic mechanism study revealed that BiOI@(BiO) 2 CO 3 has strong adsorption for RhB molecules due to the ultrathin nanosheets and higher BET, and displays better separation efficiency of photoinduced charge carriers and higher photocurrent due to the {001}/{001} facet coupling.