Polycrystalline thin films of ZnSe and ZnSxSe1−x have been deposited on glass substrates by Aerosol Assisted Chemical Vapour Deposition (AACVD) from bis(diethyldiselenocarbamato)zinc(II) and a 1:1 and 1:0.75 mixtures of bis(diethyldiselenocarbamato)zinc(II) and bis(diethyldithiocarbamato)zinc(II) as precursors. All films were characterized by p-XRD, SEM, EDX, Raman spectroscopy, photoluminescen...

The correlation of the electronic band structure with the photocatalytic activity of AgTaO3 has been studied by simulation and experiments. Doping wide band gap oxide semiconductors usually introduces discrete mid-gap states, which extends the light absorption but has limited benefit for photocatalytic activity. Density functional theory (DFT) calculations show that compensated co-doping in AgT...

Reflection electron energy loss spectra from some insulating materials (CaCO3, Li2CO3, and SiO2) taken at relatively high incoming electron energies (5-40 keV) are analyzed. Here, one is bulk sensitive and a well-defined onset of inelastic excitations is observed from which one can infer the value of the band gap. An estimate of the band gap was obtained by fitting the spectra with a procedure ...

The concentrically-layered photonic structure found in the tropical fruit Margaritaria nobilis serves as inspiration for photonic fibers with mechanically tunable band-gap. The fibers show the spectral filtering capabilities of a planar Bragg stack while the microscopic curvature decreases the strong directional chromaticity associated with flat multilayers. Elongation of the elastic fibers res...

the structure and the electronic properties of single-walled zigzag bn and b3c2n3 nanotubes (n, 0; n=4–10) were investigated using first-principles calculations based on a density functional theory. a plane–wave basis set with periodic boundary conditions in conjunction with vanderbilt ultrasoft pseudo-potential was employed. the energy gap of zb3c2n3nts was calculated and compared with the cor...

Low-temperature scanning tunneling microscopy is used to study the 2×1 reconstruction of cleaved Ge(111) surfaces. Buckling of the surface atoms is investigated by observations of the corrugation shift between filled and empty states. In the direction, the shift in corrugation maxima from filled to empty states is found to be negative, consistent with expectations for the “negatively buckled" m...

the atmospheric pressure chemical vapor synthesis (apcvs) route is a process that can be used for the synthesis of doped-nanocrystalline powders with very small crystallite sizes having a narrow particle size distribution and high purity. in this study, apcvs technique was used to prepare boron-doped titania nanopowders. the effects of temperature, borate flow rate and water flow rate on the am...