Preparation of β-Bi₂O₃/g-C₃N₄ nanosheet p–n junction for enhanced photocatalytic ability under visible light illumination

β-Bi₂O₃/g-C₃N₄ nanosheet (NS) p–n junction of g-C₃N₄ NS-wrapped β-Bi₂O₃ was fabricated via self-assembly process by electrostatic force. By the analyses of scanning electron microscopy images and Fourier transform infrared spectra, the g-C₃N₄ NS has been wrapped on the spherical β-Bi₂O₃ particles. Constructing p–n junction with g-C₃N₄ NS can enhance the separation efficiency of photogenerated carriers and light absorption ability of β-Bi₂O₃ particles obtained by the characterization of fluorescence spectra and diffuse reflectance spectra. The photocatalytic removal rate of RhB is largely enhanced by construction of β-Bi₂O₃/g-C₃N₄ NS p–n junctions. The photocatalytic ability of β-Bi₂O₃/g-C₃N₄ NS p–n junctions can be adjusted by tuning the loading amount of g-C₃N₄ NS. The enhanced photocatalytic performance is firstly attributed to the p–n junction effect of efficient separation of photogenerated charge carriers. Furthermore, the increased light absorbance of the composites also contributes to the enhanced photocatalytic ability