Sono-precipitation of Ag2CrO4-C composite enhanced by carbon-based materials (AC, GO, CNT and C3N4) and its activity in photocatalytic degradation of acid orange 7 in water

• Successfully synthesis of Ag 2 CrO 4 -C nanocomposites by sono-precipitation method. • Efficient photocatalytic activity of Ag 2 CrO 4 in composites with carbon based materials. • The highest photocatalytic activity of Ag 2 CrO 4 -C 3 N 4 nanocomposite. • Kinetic consideration of synthesized composites toward removal of dye from wastewater. • Reaction mechanism for dye removal over Ag 2 CrO 4 -g-C 3 N 4 nanocomposite. Enhancing the photocatalytic activity of Ag 2 CrO 4 with coupled carbon-based materials like activated carbon, graphene oxide, carbon nanotubes and carbon nitride has been investigated in removal of Acid Orange 7 from wastewater. Sono precipitated Ag 2 CrO 4 -C composite based photocatalysts were characterized by XRD, BET, FESEM, FTIR and UV–vis DRS and the photocatalytic activity of theses samples was evaluated in terms of degradation amount of acid orange 7 under visible light irradiations. BET analysis showed that with addition of carbon based materials, the specific surface area of the Ag 2 CrO 4 -C composite increased. XRD analysis indicated that the crystallinity of Ag 2 CrO 4 peaks decreased after addition of all studied carbon-based materials and C 3 N 4 has lowered the crystallinity of Ag 2 CrO 4 less than others. Higher crystallinity has the positive effect of higher photocatalytic activity because among above mentioned composites, Ag 2 CrO 4 -C 3 N 4 photocatalyst exhibited higher photocatalytic activity and stability under visible light irradiations. DRS analysis confirmed good match of electronic structures of Ag 2 CrO 4 and C 3 N 4 . On the other hand Ag 2 CrO 4 and C 3 N 4 formed heterojunction which separates photo-generated electron-hole pairs effectively. Also evaluation of photocatalytic reaction in various operating parameters showed Ag 2 CrO 4 -C 3 N 4 had the highest photocatalytic activity in neutral pH and 1 g/L of catalyst loading.