Generation of novel, hygienic, inhibitive, and cost-effective nanostructured Core-shell pigments

Abstract

The key goal of this study is to develop new, eco-friendly, and cost-effective nanostructured core-shell pigments based on nanosilica extracted from rice husk agro-waste to offer both anticorrosive and antimicrobial characteristics. The nanostructured core-shell pigments were created by depositing a thin shell of ZnO and/or CuO nanoparticles over a low-cost core of nanosilica extracted from rice husk agricultural waste. The synthesized pigments were characterized using X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy-dispersive X-ray, and transmission electron microscopy. These pigments were incorporated into alkyd resin to evaluate their antimicrobial and anticorrosive performance. Immersion tests, electrochemical impedance spectroscopy, and scanning electron microscopy were used to determine the corrosion resistance of coatings containing the prepared nanostructured core-shell pigments. The results deduced that the coating resistance followed the sequence ZnO.CuO/Si > ZnO/Si > CuO/Si > nanosilica. Furthermore, the antimicrobial activity of these coatings was investigated using disk diffusion and shake flask methods. The results revealed that coatings containing the prepared pigments could offer good antimicrobial activity. This research shows that these novel nanostructured core-shell pigments may act as anticorrosive and antimicrobial pigments in a single-layered coating at a low cost. Additionally, because they are constructed mainly of nano-silica recovered from agro-waste and have a low concentration of heavy metals, these pigments are both cost-effective and eco-friendly.