The ternary chalcopyrite semiconductors I-III-VI are currently used for photovoltaic solar cell applications. In this study, AgIn5S8 thin films were prepared from a series of single-source bimetalorganic precursors, e.g. [(PPh3)2AgIn(SC{O}R)4] (R = alkyl) by aerosol assisted chemical vapour deposition (AA-CVD). The compounds can be used as single-source precursors for the deposition of ternary compounds (I-III-VI) by one-pot reaction using CVD process and they are found to be air stable, which is favourable in comparison with metal alkyl compounds, which are found to be pyrophoroic. The optimum growth temperature for the preparation of these films on glass and Si(100) substrates, was found to be above 350°C in terms of crystallinity, although deposition occurred at low temperatures. The films have been investigated using XRD, SEM and EDS. SEM analysis shows that all films are microcrystalline but have different morphologies depending on the growth temperatures. XRD results show evidence of the crystalline nature of these films. The results of this comprehensive study are presented and discussed.

The study of nano-cylinder structure has attracted much attention due to the application of multi-wall carbon nanotubes (MWCNTs). While some TEM observations indicate that they are formed by seamless concentric cylinders, other TEM and high pressure X-ray diffraction studies suggest that they look like scrolls of graphite sheets. Although many people now accept the concentric cylinder model, there has been no confirmation reported. On the other hand, this structural difference of MWCNTs plays a crucial role in determining the properties and suitability for future applications. For example, the periodical boundary condition can only be imposed for cylinders, but not for scrolls. To resolve this issue, we employed high-resolution X-ray diffraction to measure detailed profiles of the Bragg peaks for high-purity MWCNTs. We then identified some unusual observations unique to the nano-cylinder structure, followed by the analysis of the structural difference in the Fourier transform between nanotubes formed by scrolls and concentric cylinders. The simulation results are then compared with the experimental data to reveal the structural details.