Synthesis and Characterization of Some Halides and Chalcogenide Crystals Using Sol-Gel Method.

Abstract In this research work, sol-gel technique was used to grow some crystals of halide and chalcogenide compounds. These grown crystals were doped with locally produced dopants from bamboo, raffia and potash to see how they can affect the optical and structural properties of the crystals. Dopants were produced from local materials using top down approach where bulk materials (bamboo, potash and raffia) were whittled down through burning into carbon dioxide, water and residual ashes containing a lot of elemental carbon in the form of soot. The residual ashes were dissolved in water, placed in a centrifuge to remove solid particles. Appropriate quantity of the supernatant liquid was added to the gel as dopant. In some growths, the gel was allowed to age at room temperature for periods of 5, 15 or 25 days before they were dried in an oven at a temperature of 104o C for 30 minutes. CaCl2 was used as desiccant. Subsequently, they were characterized to determine their optical and structural properties using a JENWAY 6405 UV-VIS spectrophotometer operating at a wavelength range of 200nm to 1200nm at intervals of 5nm and MD-10 Diffractometer, X-ray diffraction machine respectively. The X Ray Diffraction (XRD) and Fourier Transform Infra Red (FTIR) spectroscopy showed that the locally made dopants are crystalline, nano polymers. The presence of locally produced dopants have enabled us to grow and discover hybrid compounds of binary, ternary and quaternary constitutions; Halloysite [Al2Si2O5(OH)4!2H2O], Sekaninaite (Fe2Al4Si5O18), Illitre [K0.7Al2(Si,Al)4O10(OH)2], Moganite (SiO2), Ungarettite (Na3Mn5Si8O24), Clinoferrosilite (FeSiO3), Wollastonite (CaSiO3), coesite (SiO2), Vanthoffite [Na6Mg(SO4)4] that can be employed in solar energy, solid state and materials industries. Therefore, we suggest that African materials be used in the growing of crystals for further discoveries and enhanced output.