Green synthesis of ZnO NPs using aqueous extract of Epipremnum aureum leave: Photocatalytic degradation of Congo red

Abstract

The present perspective describes green synthesis of ZnO nanoparticles (NPs), a prominent semiconductor having high band gap (3.73 eV), from an aqueous extract of Epipremnum aureum leave. Several spectroscopic and analytical techniques, including UV–Vis, FT-IR, XRD, SEM, EDX, and TGA confirmed the bio-synthesis of ZnO NPs. The XRD analysis ratified the hexagonal crystalline structure of ZnO NPs with a tiny size found as 19.31 nm. An approximately similar size (29 nm) was noticed from an SEM study with a great extent of thermal stability up to 160 °C. Apart from these, UV–Vis, and FT-IR spectra confirmed the initial formation of NPs and functional groups derived from plant leaves associated with NPs. The prominent application of this study was to appraise the photocatalytic degradation of Congo red using ZnO NPs through batch study. The optimum photocatalytic degradation was attained as concentration (10 ppm), pH (2), catalyst dosage (20 mg), and contact time (100 min) for the current study. Results also divulged the good fitting of Langmuir isotherm, followed by Freundlich, Temkin, and Elovich isotherm. Furthermore, the kinetic data bolstered pseudo-second-order kinetics.

Keywords

• ZnO NPs
• Epipremnum aureum
• Photocatalyst
• Congo red