Bio-mediated synthesis of ZnO nanostructures for efficient photodegradation of methyl orange and methylene blue

Abstract

We report herewith the Syzygium cumini leaf extract-mediated synthesis of nanostructures of ZnO as a green approach. The XRD pattern shows that the ZnO NSs associate to the hexagonal wurtzite structure. From DRS, the band edge is found to be 393 nm (Eg\u2009=\u20093.16 eV). The FT-IR spectrum of ZnO shows the formation of Zn–O bond, and SC plant extract shows the presence of -CHO, -NH2, aromatic rings, and -OH groups that are responsible for the biochemical conversion. The TEM images show that the synthesized ZnO NSs are in spherical shape with the particle size of 25–30 nm. The photodegradation efficiency of ZnO NSs was determined under UV–Vis light using methyl orange and methylene blue as model dye pollutants. The photodegradation reaction follows pseudo-first-order kinetics with 88% efficiency for MO degradation within 150 min, whereas 84% for MB within 60 min under UV–Vis. light.