Fabrication of PET/BiOI/SnO2 heterostructure nanocomposites for enhanced visible-light photocatalytic activity

Heterojunction BiOI/SnO2 nanocomposites have been facilely synthesized by using successive ionic layer adsorption and reaction (SILAR) and a hydrothermal method, and polyethylene terephthalate (PET) nanofibers (NFs) were utilized as a photocatalyst carrier to support the BiOI/SnO2 nanocomposites. PET/BiOI/SnO2 NFs displayed excellent photocatalytic ability towards methyl orange (MO) and tetracycline (TC) under visible light irradiation. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to investigate the morphology, crystal structure and chemical state of the PET/BiOI/SnO2 nanofibers. Photoluminescence (PL) and active species trapping experiments indicated that photoinduced charge separation promoted the formation of holes (h(+)) and superoxide radicals (center dot O--(2)). Moreover, a photodegradation mechanism was proposed to illustrate that the formation of a Fermi level equilibrium state between semiconductors accelerated charge separation in the semiconductor. This study is meaningful for providing new inspiration to design and fabricate novel heterostructure photocatalysts with enhanced photocatalytic activity.