With a view to contribute to the understanding the surface effects on optical properties process, and its hole in the electronic properties of the nanoparticles, CdS based nanoparticles are characterised by different experimental techniques and the experimental results compared to density functional theory calculations. Our results indicate that cubic CdS nanoparticles present a strong structural deformation, hexagonal reconstructed structures preserve their lattice behaviour. Both cubic and hexagonal CdS nanoparticles are S-terminated after relaxation, even when mildly Cd-rich nanoparticles are considered. A broad peak observed in our PL measurements is interpreted as an experimental evidence of the surface related peak observed around 1.8 eV in our calculated DOS for the hexagonal relaxed structure.
Comparative study of nanosized magnetite and magnetite suspended in Copaiba oil (biocompatible magnetic fluid) was made using Mössbauer spectroscopy with a high velocity resolution (spectra were measured in 4096 channels). The better fit of room temperature spectra was done using 15 sextets and 1 doublet employing different parameters while spectra measured at 90 K were better fitted using 15 sextets with different parameters. These component numbers were related to multi-domain structure and non-stoichiometry of magnetite. Observed differences of magnetic hyperfine fields and relative areas of spectral components for nanosized Fe 3 O 4 and Fe 3 O 4 suspended in Copaiba oil may be related to the effect of surface interactions of Fe 3 O 4 and polar molecules of Copaiba oil.
CdS nanocrystals were prepared using a standard colloidal route (co-precipitation chemical reaction) whereas modulation of the optical and structural properties was realized via surface coating the nanocrystals with ethylene glycol molecules using an in situ procedure. The as-produced nanocrystals were characterized by X-ray diraction, Raman spectroscopy, UV-absorption measurements and photoluminescence. The nanocrystal quality was revealed by the spectroscopic data, though the nal product presents a mixture of both zinc blende (cubic) and wurtzite (hexagonal) phases. The X-ray data indicated that the concentration of the ethylene glycol used during the synthesis process modulates the nanocrystal size and the crystal phase of the end material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.