Department of Chemistry

Permanent URI for this collection

https://repository.udsm.ac.tz/handle/123456789/82

Browse

Browsing Department of Chemistry by Author "Akerman, Matthew P"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Deposition of Bi2S3 thin films from heterocyclic bismuth (III) dithiocarbamato complexes.
    (Polyhedron, 2018) Kun, Walter N; Mlowe, Sixberth; Nyamen, Linda D; Akerman, Matthew P; O'Brien, Paul; Ndifon, Peter T; Revaprasadu, Neerish
    Two heterocyclic dithiocarbamate complexes, tris- (piperidinedithiocarbamato)bismuth(III) (1) and tris-(tetrahydroquinolinedithiocarbamato) bismuth(III) (2) were synthesized and characterized by elemental analysis and thermogravimetric analysis. The structure of complex (1) was confirmed by single-crystal X-ray analysis. Both complexes were used as single source precursors for the deposition of bismuth sulfide thin films by aerosol assisted chemical vapour deposition (AACVD) at 350, 400, 450 °C and spin coating followed by thermal treatment at 350 °C, 400 °C and 450 °C. Both deposition methods, gave sulfur deficient polycrystalline films of bismuthinite. Scanning electron microscopy (SEM) images of the films showed morphology was dependent on the solvent mixture, temperature, precursor type and method of deposition. AACVD gave films with hexagonal nanoplatelets, leaf-like platelet, ribbon-like fibre, needle-like fibre morphologies. Films in the form of rods and interwoven nanowires were obtained from spin coating.
  • No Thumbnail Available
    Item
    Heterocyclic lead(II) thioureato complexes as single-source precursors for the aerosol assisted chemical vapour deposition of PbS thin films
    (Inorganica Chimica Acta, 2018) Ketchemen, Kevin IY; Mlowe, Sixberth; Nyamen, Linda D; Aboud, Ahmed A; Akerman, Matthew P; Ndifon, Peter T; O'Brien, Paul; Revaprasadu, Neerish
    The lead N’-benzoylthioureato complexes of N-morpholine (1) and N-pyrrolidine (2) were synthesized and characterized by elemental analysis, Fourier Transform Infra-Red (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H nmr) and thermogravimetric analyses (TGA). The X-ray single crystal structure of complex (1) was determined. The compounds were both used as single source precursors to deposit PbS films on glass substrates at 350, 400 and 450 °C using aerosol assisted chemical vapour deposition (AACVD) The surface morphology of PbS films were determined by scanning electron microscopy (SEM), the crystalline phases established by powder X-ray diffraction (p-XRD) analyses and composition by energy dispersive X-ray spectroscopy (EDX). The particle sizes were found to range between 82 and 85 nm from complex (1) and 70–105 nm for (2) The PbS films were studied by Near Infra-red (NIR) UV–Vis spectroscopy, band gap ranging from 1.46 to 1.55 eV were observed.
  • No Thumbnail Available
    Item
    Phase pure Ni3S2 and NiS from bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) via solvent thermolysis and aerosol assisted chemical vapour deposition.
    (New Journal of Chemistry, 2018) Gervas, Charles; Mlowe, Sixberth; Akerman, Matthew P; Revaprasadu, Neerish
    A bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) complex was prepared and characterized using infrared spectroscopy, thermogravimetric and elemental analyses. The crystal X-ray structure for bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) was determined. The complex was subsequently used as a single source precursor (SSP) for the synthesis of phase pure Ni3S2 and NiS nanoparticles and thin films via hot injection thermolysis and aerosol assisted chemical vapour deposition (AACVD) routes, respectively. For the hot injection thermolysis route, hexadecylamine (HDA) and oleylamine (OLA) were used as capping groups at varying temperatures. Chloroform was used as the solvent in the AACVD experiments. Powder X-ray revealed that the capping group does not change the phase of nanoparticles formed whereas the AACVD technique produced different phases. Variation of temperature did not affect the phase purity of the nanomaterials formed. The morphology of the thin films obtained via AACVD depended largely on the deposition temperature, whereas for the nanoparticles, temperature and the capping group had a significant impact.