Curcumin‐Functionalized Ag/Ag₂O Nanocomposites: Efficient Visible‐Light Z‐scheme Photocatalysts

Abstract

Curcumin-functionalized Ag/Ag O (c-Ag/Ag O) nanocomposites with varying proportions of curcumin and Ag/Ag O were prepared by a simple one pot green synthesis protocol in aqueous medium. The plasmonic band undergoes slight redshift, broadening and decrease in intensity with increase in the proportion of Ag O formed. These composite nanoparticles were found to be efficient visible-light photocatalysts for aerobic oxidation of methyl orange and rhodamine B (RhB). Functionalization by curcumin significantly enhanced the photocatalytic activity with good reusability. The photocatalytic oxidation rate showed super linear increase with light intensity because of localized surface plasmon resonance (LSPR)-induced strong near field. The trapping experiments confirmed that superoxide radicals were the main active species responsible for the degradation reaction. A plasmonic Z-scheme photocatalytic mechanism is proposed to explain the possible charge transfer and separation behavior of electron-hole pairs among Ag, Ag O and curcumin under visible-light irradiation.

Green Synthesized of Ag/Ag2O Nanoparticles Using Aqueous Leaves Extracts of Phoenix dactylifera L. and Their Azo Dye Photodegradation

“…Ag 2 O generally exhibits a narrow direct bandgap of 1.2–1.4 eV. Assuming a bandgap of about 1.4 eV, the edge positions of the valence band and conduction band are determined to be 0.09 and 1.49 eV, respectively [ 28 ]. Previously, under the induction of fluorescence, Ag 2 O has succeeded in decolorizing an aqueous solution of anionic dyes (methyl orange) at a rate constant of 0.023 min −1 , demonstrating its photocatalytic efficiency [ 12 ].…”

Promoting Effect of Silver Oxide Nanoparticles on the Oxidation of Bisphenol B by Ferrate(VI)

“…It can be seen that the oxidation reaction of the Fe­(VI)–Ag 2 O system greatly reduces the hydrodynamic diameters of Ag 2 O, which was consistent with the morphology characterization result. In addition, crystalline phases of Ag 2 O catalyst were determined by a Brooke D8 Discover XRD diffractometer using 100 mA, 40 kV, Cu Kα radiation at the 2θ range of 20–80°. , As seen in Figure H, the XRD peaks of the catalyst before and after the reaction were indexed to Ag 2 O (JCPDS 75-1532). The peaks at 26.7°, 32.9°, 38.1°, 55.0°, 65.6°, and 68.9° correspond to the (110), (111), (200), (220), (311), and (222) planes of Ag 2 O, respectively.…”

Performance evaluation of Zr(CUR)/NiCo2S4/CuCo2S4 and Zr(CUR)/CuCo2S4/Ag2S composites for photocatalytic degradation of the methyl parathion pesticide using a spiral-shaped photocatalytic reactor

“…Curcumin acts as a photosensitizer owing to an appropriate HOMO-LUMO gap in the visible range. 25 Curcumin can be coupled with wide band gap photocatalysts to produce visible-light-driven photocatalyst. 26 It gets photo-excited when the material is illuminated with visible light.…”