Construction of ZnO nanoparticles on the layered aluminosilicate Montmorillonite K30 nanocomposite and its enhanced photocatalytic removal performance

Abstract

In this present investigation, we have synthesized spherical ZnO nanoparticles via Carrisa edulis fruit extract through ultrasonication technique. The layered aluminosilicates of montmorillonite K30 (MK30) with varied ZnO nanoparticles (ZnO NPs) loadings have been achieved through ultrasonication method. The samples were systematically characterized by XRD, FT-IR, FE-SEM, HR-TEM, N2-adsorption-desorption isotherm, Zetapotential, UV–Vis DRS, EIS and PL. HR-TEM revealed the existence of nano spherical-shaped ZnO with an average particle size of 40.75 nm. According to the FE-SEM and EDS elemental mapping findings, ZnO nanoparticles were evenly distributed across the surface of the MK30. The acquired results showed that the 20% ZnO loaded MK30 nanocomposite exhibited a significant adsorption and degradation rate. According to PL and EIS experiments, the greater charge separation and extended UV light absorption that followed the interfacial charge transfer route are responsible for these improved photocatalytic activities. The findings showed that MB was entirely degraded within 90 min at about 95.76% efficiency. In addition, the photocatalytic degradation process was found to be in accordance with the pseudo-first-order kinetic model, with the degradation rate constant of 20ZnMK30 being calculated to be 2.86 × 10−2 min−1. Results from different scavenging study indicate that OH and superoxide radical act as main reactive species in photodegradation of MB. Further, the photocatalyst sustained a high level of stability for up to 5 cycles with a minor decrease in activity. The findings of this work would be beneficial for energy and environmental applications with all sustainable systems.