Browsing by Author "Morad, R"

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    Bio-synthesised black α-Cr2O3 nanoparticles; experimental analysis and density function theory calculations
    (Elsevier, 2021) Kotsedi, Lebogang; Sackey, Juliet; Morad, R
    A selective single phase black α-Cr2O3 nanoparticles was bio-synthesised via simple straight-forward green synthesis approach. The process involves extraction of phytochemicals contained in peels of sweet potatoes. Extraction was done in distilled water under constant magnetic stirring at a temperature of 70–80 °C resulting in a dusty yellow colour aqueous extracts. Afterwards, chromic nitrate salt was added to extracts resulting in reduction of metal salt to metal nanoparticles. Obtained precipitates were dried and annealed in the air for 2 h ready to be applied without further post synthesis modifications. SEM and EDS analysis of annealed precipitates reveal distinct shapes and high purity of nanoparticles. The effects of the annealing temperature are evident in the nanoparticle sizes. SAED and XRD patterns expose bright diffraction peaks which are harmonized to the rhombohedral structure of pure Eskolaiteα-Cr2O3. By quantitative analysis of XRD data, it was noted that lattice parameters and crystal sizes slightly decrease w.r.t increase annealing temperature.
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    Synthesis, characterization and ab initio study of WO3 nanocubes with peculiar electrochemical properties
    (Springer, 2021) Bashir, A. K.H; Morad, R; Nwanya, A. C; Akbari, M; Sackey, J; Kaviyarasu, K; Madiba, I. G; Ezema, F. I; Maaza, M
    Simple sol–gel method has been exploited to deposit Sn-doped TiO2 thin flms on glass substrates. The resultant coatings were characterized by X-ray difraction (XRD), UV–visible techniques (UV–Vis), Fourier transform infrared spectroscopy (FTIR), and photoluminescence analysis (PL). The XRD pattern reveals an increase in crystallite size of the prepared samples with the increasing doping concentration. A decrease in doping concentrating resulted in the decrease in bandgap values. The diferent chemical bonds on these flms were identifed from their FTIR spectra. The photoluminescence analysis shows an increase in the emission peak intensity with increasing dopant concentration, and this can be attributed to the efect created due to surface states. The prepared samples were tested as antibacterial agent toward both Gram-positive and Gram-negative bacteria like S.aureus (Staphylococcus aureus) and E.coli (Escherichia coli), respectively. The size of the inhibition zones indicates that the sample shows maximum inhibitory property toward E.coli when compared to S.aureus.