Facile preparation of Ag/Ag2WO4/g-C3N4 ternary plasmonic photocatalyst and its visible-light photocatalytic activity

Introducing plasmonic metals into semiconductor materials has been proven to be an attractive strategy for enhancing photocatalytic activity in the visible region. In this work, a novel and efficient Ag/Ag2WO4/g-C3N4 (AACN) ternary plasmonic photocatalyst was successfully synthesized using a facile one-step in situ hydrothermal method. The composition, structure, morphology and optical absorption properties of AACN were investigated using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and UV-visible diffuse reflectance spectroscopy, respectively. Photocatalytic performance of AACN was evaluated via rhodamine B and tetracycline degradation. The results indicated that AACN had excellent photocatalytic performance for rhodamine B degradation with a rate constant of 0.0125 min(-1), which was higher than those of Ag2WO4 and Ag/Ag2WO4. Characterization and photocatalytic tests showed that the strong coupling effect between the Ag/Ag2WO4 nanoparticles and the exfoliated ultrathin g-C3N4 nanosheets was superior for visible-light responsivity and reduced the recombination rate of photogenerated electrons and holes. A proposed mechanism is also discussed according to the band energy structure and the experimental results.