Abstract:

The purpose of this study is to prepare and characterize Nickel cobaltite nanoparticles, then three promising applications of NiCo2O4 nanoparticles; namely hyperthermia heating, adsorption of heavy metals ions and nanotoxicity, were investigated.

NiCo2O3 nanoparticles was prepared by milling a mixture of NiO and Co3O4 powder, then annealing at 600C for three different time intervals. The as-received, milled and annealed powders were characterized using X-ray powder diffraction for structural analysis, as well as scanning electron microscopy coupled with energy dispersive x-ray spectroscopy for morphology and elemental chemical composition. Furthermore, the magnetic properties are studied using vibrating sample magnetometer.

The hyperthermia effect (temperature versus time in varying magnetic field) at two concentrations 10 and 15 mg/ml of nanoparticles dispersed in distilled water was studied. Then, specific absorption rate (SAR) was calculated and the relation between the SAR and magnetic properties is discussed.

Cd2+ and Pb2+ adsorption capabilities were deduced; the Pb and Cd ions residues, removal percent efficiencies, and adsorption capacities of the prepared nanopowders in acidic and basic environments at three different dosage of nanoparticles were estimated. Moreover, the as-obtained results were compared to literature in order to figure out the optimum conditions for heavy metal removal.

The nanotoxicity on a microalgae Chlorella vulgaris was investigated by two factors; i.e. viable cells and chlorophyll a. The mean number of viable cells in C. Valgris culture treated with nanoparticles was compared with control culture in 4 days. Similarly, the mean chlorophyll a of treated cultures was compared to control culture for 4 days. ANOVA tests at significance of 95% were applied on the mean values to check the toxicity of the studied nanoparticles.