Graphene Oxide (GO) was chemically synthesized from Natural Flake Graphite (NFG). The GO was chemically reduced to Reduced Graphene Oxide (RGO) using hydrazine monohydrate. Thin films of GO and RGO were also deposited on sodalime glass substrate using spray pyrolysis technique (SPT). The samples were characterized using Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray (EDS) facility attached to it, UV-Visible Spectrometry and Four-Point probe. The FTIR spectra showed the addition of oxygen functionality groups in GO while such groups was drastically reduced in RGO. SEM micrograph of GO thin film showed a porous sponge-like structure while the micrograph of RGO thin film showed evenly distributed and well connected graphene structure. The EDX spectrum of RGO showed that there was decrease in oxygen content and increase in carbon content of RGO when compared to GO. The optical analysis of the GO and RGO thin films gave a direct energy bandgap of 2.7 eV and 2.2 eV respectively. The value of sheet resistance of GO and RGO films was determined to be 22.9 × 10 6 Ω/sq and 4.95 × 10 6 Ω/sq respectively.

A single solid source precursor bis-(morpholinodithioato-s,s')-Mo was prepared and molybdenum sulphide thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD) technique at deposition temperature of 420˚C. The film was characterized using Rutherford Backscattering Spectroscopy (RBS), Ultraviolet-Visible Spectroscopy, Four-point Probe technique, Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD) and Atomic Force Microscopy (AFM). A direct optical band gap of 1.77 eV was obtained from the analysis of the absorption spectrum. The sheet resistance was found to be of the order of 10-5 Ω-1 •cm-1. SEM micrographs of the films showed the layered structure of the film with an estimated grain size that is less than 2 µm while XRD indicates parallel orientation of the basal plane to the substrate surface.

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Microporous ceramic matrix membranes were prepared with complementary proportions of locally available zeolitic aluminosilicate materials and other abundant lateritic clay minerals. The membranes cast as circular disks (22.78 mm diameter and 2.11 mm thickness) were treated with silver nitrate solution to discourage microbial growth on their surface and then sintered at C for about 20 hours. Antimicrobial microfiltration process showed 87.24% to 100% bacterial rejection depending on the material combination ratio. Elemental characterization of the membrane materials was done using ion beam analysis (IBA) technique of particle induced X-ray emission (PIXE), while the physicochemical behaviour of the ceramic membranes was carried out through the analysis of the filtered water samples using atomic absorption spectroscopy (AAS), total dissolved solids (TDS), microbial, and pH analyses. Compositional characterization of raw materials showed comparatively low contents of impurities, such as Fe and Ca, in the raw materials, but with high SiO2/Al2O3 ratios for the raw material which is important for zeolitic material synthesis. Regularly porous microstructure of mean pore diameter of between 50 nm and 100 nm was observed from the analyzed images obtained from ZEISS Supra 40 scanning electron microscope.