1,721,018 research outputs found
Influence of thermal annealing on the optical absorption and dark conductivity of amorphous gallium sulfide thin films
No full text
Investigation of electronic properties of gallium sulfide single crystals grown by iodine chemical transport
No full textShort-range ordered 2D nanoholes: lattice-model and novel insight into the impact of coordination geometry and packing on their propagating-mode transmittance features
No full textOptically thin perforated gold films, fabricated using template colloidal masks self-assembled by following an elsewhere described simplified colloidal lithography protocol, are presented and discussed with the aim to develop a theory of short-range ordered nanoholes without straightforwardly extending concepts strictly related to periodic nanoholes. By Scanning Electron Microscopy (SEM) analysis of the evolution of nanohole short-range ordering and spatial coordination geometry under increasing interhole average spacing (d(NN)), unprecedented differences in the spectroscopic response are pointed out with respect to periodic systems. First, the dependence of the wavelength of a propagating plasmon mode on d(NN) is demonstrated to deviate from the linear relationship predicted by the grating-coupling picture developed for periodic arrays. Second, d(NN) cannot be straightforwardly interpreted as the counterpart of the lattice constant of periodic nanoholes, which demands to introduce a conceptually more rigorous periodicity-like length-scale. Once the impact of these findings on setting the operating parameters of a nanohole distribution is demonstrated, they are related, experimentally and by using a theoretical model developed by the authors, to the changes of the local coordination geometry (from quasi-hexagonal to quasi-square packing through mixed hexagonal–square coordination) induced by varying d(NN) over a wide interval. Autocorrelation analysis of SEM images is exploited to estimate a short-range periodicity-like length-scale, as a conceptual advance for laying the foundation of the concept of short-range ordered nanohole lattices and for deeper insight into the spectral response. As discussion is based on realistic, rather than simulated, evolution of colloidal arrangements, the formulated interpretative model accounts for realistic effects impacting transmission resonances
C-nitroso compounds as novel promising substances for the deposition of LB films
Full text linkC-nitroso compds. and their complexes with transition metals have never been used before in Langmuir expts. Some π-A isotherms were registered for several C-nitroso derivs. For 2 metal complexes (Pd(II) and Rh(I)), thin films were deposited by the std. vertical dipping method. UV-visible spectroscopy was performed to analyze the absorption bands of the deposited films. Measurements of the dependence of the elec. cond. were carried out between 300 and 450 K. All samples display an activated elec. cond. at high temp. and related activation energies were detd. A decrease of the activation energy is reported for the Pd complex thin films into a flux of air and ppm NO2. Platinate(1-), trichloro(2-methyl-2-nitrosopropane-N)-, potassium, (SP-4-2)- 68851-40-1
Deposition and characterization of nitroso compound LB films
No full textThin films of presynthesized N-Me-N-docosyl-p-nitrosoaniline Pd and Rh complexes were deposited by the Langmuir-Blodgett technique on hydrophobic glass and quartz substrates. The homogeneous films were characterized by UV-VIS spectroscopy and elec. measurements; they have potential use as NO2 gas sensors
Hall effect and deep level transient spectroscopy measurements in indium selenide doped with chlorine
No full text- …
