Preparation and evaluation of a hierarchical Bi₂MoO₆/MSB composite for visible-light-driven photocatalytic...

In this study, waste mussel shells were used to remove dyes in aqueous solution. Mussel shell was prepared into mussel shell biochar (MSB), which was used as a carrier to support Bi₂MoO₆. A novel Bi₂MoO₆/MSB composite photocatalyst was developed by the hydrothermal synthesis method. The as-synthesized sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N₂ adsorption-desorption method, Fourier transform infrared spectroscopy (FTIR) and UV-vis diffuse reflectance spectra (DRS). Then, the photocatalytic activity of the prepared samples was determined by testing the photodegradation of Rhodamine B (RhB) under visible-light (λ > 420 nm) irradiation. The pre exfoliated layered MSB was an excellent supporting matrix for the growth of Bi₂MoO₆ nanoflakes. The obtained hierarchical Bi₂MoO₆/MSB composites exhibited significantly enhanced performance for photocatalytic degradation of RhB compared with pure Bi₂MoO₆ under visible light irradiation because of the improved electron-hole pair separation, which boosted the number of exposed catalytic active sites. Moreover, the Bi₂MoO₆/MSB composite photocatalyst is of good stability and reusability.