Synthesis of C. Benghanlensis NiO NPs for the degradation of malachite green and the removal of bacteria

Abstract

An increase in environmental pollution has affected human lives, where water scarcity due to water pollution and climate change is on the rise. The increase in the usage of dyes such as malachite green in the textile industry and bacteria has increased the different types of pollutants found in the water streams, hence the need to remove these pollutants. NiO nanoparticles (NiONPs) were formed using Commelina benghalensis plant extract as a reducing agent. These materials were characterized using PL, XRD, VSM, TGA, FTIR, UV–Vis and BET. XRD identified the phases present in the material. The phytochemicals present were detected using FTIR. UV–vis was used to analyze the material's formation and optical properties, and the bandgap was calculated to be 3.8 eV The average pore size was confirmed to be 10.44 nm, indicating that the material is mesoporous in nature. From VSM, the NiO NPs were shown to have paramagnetism and through TGA, a high thermal stability of the nanomaterial was observed. At optimum conditions (pH 3, 30 mg and 5 ppm) a 95% degradation of MG was achieved and these materials were recyclable for more than 3 times whilst maintaining a degradation of 90% and above. Testing this material using real water samples sampled from the tap, pond and sewage, the NiO material was more potent against S.aureus compared E.coli bacterial strains. These results indicate the material can be used for multifunctional removal of various pollutants.