Room-temperature synthesis of BiOI/Graphene oxide foam composite for phenol removal under visible light

The coupling of graphene-based materials is a widely adopted method to effectively separate photo-induced electrons and holes, and consequently, improve the performance of photocatalysts. However, the surface modification of semiconductors with graphene materials can block incident light; this is undesirable for the activity enhancement of photocatalysts. To solve this problem, a composite of graphene oxide foam coated with bismuth oxyiodide (GOF-BiOI) was synthesized at room temperature using an in-situ deposition approach. In the composite, BiOI flake arrays stand vertically and uniformly on the surface of GOF. Furthermore, the as-prepared GOF-BiOI exhibited a higher photocatalytic activity than BiOI and GO-modified BiOI for the oxidization of phenol under visible light. Based on a collective analysis of the reactive species, photoluminescence, light absorption, textural and morphological properties, the enhanced photocatalytic activity of GOF-BiOI was attributed to the electron trapping role of GOF, which effectively suppress charge recombination, and to the unique structure of GOF-BiOI, which favored not only light absorption but also the attachment of reactive materials and the surface of BiOI.