Bismuth Molybdate Nanoplates Supported on Reduced Graphene Oxide: An Effective Nanocomposite for the Removal of Naphthalene via Adsorption-Photodegradation

Abstract

Polycyclic aromatic hydrocarbons are a class of persistent organic water pollutants that raise serious concerns owing to their carcinogenicity and other negative impacts on humans and ecosystems. In this study, Bi2MoO6/reduced graphene oxide (rGO) nanocomposites were designed and prepared for the adsorption-assisted photodegradation of naphthalene molecules in an aqueous medium. The synthesized Bi2MoO6 nanoplates and Bi2MoO6/rGO nanocomposites were characterized by X-ray diffraction, Fourier transform infrared, scanning electron microscopy, high-resolution transmission microscopy, X-ray photoelectron spectroscopy, ultraviolet spectroscopy, Brunauer-Emmett-Teller, and photoluminescence measurements. The photodegradation of naphthalene molecules was observed to assess the photocatalytic characteristics of the samples under visible light. The Bi2MoO6/rGO nanocomposites exhibited significantly improved photocatalytic efficiency compared to pure Bi2MoO6. Among the nanocomposites, those containing 2 wt % rGO showed the best photocatalytic activity. The incorporation of rGO enhanced the visible light absorption and decreased the recombination rate of photogenerated charge carriers. Moreover, a Bi2MoO6/rGO nanocomposite showed excellent reusability for five cycles.