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 dep...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 Mi-croscopy (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 10P–5P ΩP–1P?cmP–1P. 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.展开更多
Graphene oxide (GO) was chemically synthesized from natural flake graphite (NFG) using the simplified Hummers method. The synthesis was carried out using two routes. The first route involved stirring the one pot mixtu...Graphene oxide (GO) was chemically synthesized from natural flake graphite (NFG) using the simplified Hummers method. The synthesis was carried out using two routes. The first route involved stirring the one pot mixture continuously for three days at ambient temperature while the second route involved stirring another one pot mixture for six days also at ambient temperature. The two GOs were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-Ray Spectroscopy (EDX), Field Emission Scanning Electron Microscopy (FE-SEM), Raman Spectroscopy and UV-Visible Spectrometry. The FTIR spectra showed introduction of oxygen functionalities in both GO with a higher degree of oxidation in the 6-day synthesized GO while the EDX confirmed the presence of carbon and oxygen in the GOs. The SEM micrograph gave the typical wrinkle and crumpling present in the 3-day synthesized GO while the 6-day synthesized GO showed distortion in structures. The Raman spectra showed a slightly higher ID/IG ratio for the 3-day synthesized GO with the 6-day synthesized GO showing a greater disruption of the sp2 domains. The extended period of stirring and oxidation increased the band gap of the 6-day synthesized GO to 3.0 eV unlike the 3-day synthesized GO where 2.5 eV was observed.展开更多
Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the depo...Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the deposition temperature of 420°C. The deposited films were characterized using Rutherford Backscattering Spectroscopy, Scanning Electron Microscopy with Energy Dispersive X-Ray facility attached to it, X-Ray Diffractometry, UV-Visible Spectrometry and van-der Pauw Conductivity measurement. Results show that the thickness of the prepared film is determined as 101.236 nm and the film is amorphous in structure, having average grain size of approximately 1 μm. The optical behaviour showed that the absorption edge of the film was at 918 nm near infrared with corresponding direct energy band gap of 1.35 eV. The electrical characterization of the film gave the values of resistivity, sheet resistance and conductivity of the film as 3.43 × 10-1 Ω-cm, 3.39 × 106 Ω/square and 2.91 (Ω-cm)-1 respectively.展开更多
文摘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 Mi-croscopy (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 10P–5P ΩP–1P?cmP–1P. 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.
文摘Graphene oxide (GO) was chemically synthesized from natural flake graphite (NFG) using the simplified Hummers method. The synthesis was carried out using two routes. The first route involved stirring the one pot mixture continuously for three days at ambient temperature while the second route involved stirring another one pot mixture for six days also at ambient temperature. The two GOs were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-Ray Spectroscopy (EDX), Field Emission Scanning Electron Microscopy (FE-SEM), Raman Spectroscopy and UV-Visible Spectrometry. The FTIR spectra showed introduction of oxygen functionalities in both GO with a higher degree of oxidation in the 6-day synthesized GO while the EDX confirmed the presence of carbon and oxygen in the GOs. The SEM micrograph gave the typical wrinkle and crumpling present in the 3-day synthesized GO while the 6-day synthesized GO showed distortion in structures. The Raman spectra showed a slightly higher ID/IG ratio for the 3-day synthesized GO with the 6-day synthesized GO showing a greater disruption of the sp2 domains. The extended period of stirring and oxidation increased the band gap of the 6-day synthesized GO to 3.0 eV unlike the 3-day synthesized GO where 2.5 eV was observed.
文摘Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the deposition temperature of 420°C. The deposited films were characterized using Rutherford Backscattering Spectroscopy, Scanning Electron Microscopy with Energy Dispersive X-Ray facility attached to it, X-Ray Diffractometry, UV-Visible Spectrometry and van-der Pauw Conductivity measurement. Results show that the thickness of the prepared film is determined as 101.236 nm and the film is amorphous in structure, having average grain size of approximately 1 μm. The optical behaviour showed that the absorption edge of the film was at 918 nm near infrared with corresponding direct energy band gap of 1.35 eV. The electrical characterization of the film gave the values of resistivity, sheet resistance and conductivity of the film as 3.43 × 10-1 Ω-cm, 3.39 × 106 Ω/square and 2.91 (Ω-cm)-1 respectively.