Polyvinyl alcohol stabilized ZnS nanoaggregates using organosulfur source for photocatalytic disintegration of methyl orange dye

Abstract

ZnS nanoaggregates surface-passivated by a hydroxyl-based polymer matrix, polyvinyl alcohol (PVA), have been synthesized using a wet chemical method and an organosulphur precursor. The nanocomposite was characterized by XRD, SEM, and FTIR. XRD patterns revealed wurtzite structure. FTIR spectrum confirmed the interaction of hydroxyl group of PVA with the ZnS. We proposed a probable pathway for the precipitation of zinc sulfide by alkaline hydrolysis of complex formed from (NH2)2CS and Zn2+-polymer complex. The optical properties were monitored using UV–Vis spectroscopy and photoluminescence (PL) spectroscopy. Quantum confinement of electrons is confirmed by increase in the optical band gap and determined to be 3.91 eV. The photocatalytic activity of the ZnS/PVA nanoaggregates particles was examined using methyl orange (MO). After 3 h of illumination, the photocatalytic degradation rate of methyl orange (MO) is about 94.20 %.

Keywords

• ZnS-PVA nanoaggregates
• Optical absorption
• Photoluminescence (PL)
• Photocatalysis