A5085353356- Fullerene Chemistry and Applications
- Carbon Nanotubes in Composites
- Graphene research and applications
- GaN-based semiconductor devices and materials
- High-pressure geophysics and materials
- Diamond and Carbon-based Materials Research
- Mechanical and Optical Resonators
- Boron and Carbon Nanomaterials Research
- Semiconductor materials and devices
- Metal and Thin Film Mechanics
- ZnO doping and properties
- Luminescence Properties of Advanced Materials
- Crystal Structures and Properties
- Superconductivity in MgB2 and Alloys
- Ga2O3 and related materials
- Force Microscopy Techniques and Applications
- Astrophysics and Star Formation Studies
- Physics of Superconductivity and Magnetism
- Thermal Expansion and Ionic Conductivity
- Semiconductor materials and interfaces
- Photorefractive and Nonlinear Optics
- Gold and Silver Nanoparticles Synthesis and Applications
- Chalcogenide Semiconductor Thin Films
- Solid-state spectroscopy and crystallography
- Rare-earth and actinide compounds
Aristotle University of Thessaloniki
2015-2025
Tohoku University
2019
Advanced Institute of Materials Science
2019
Institute for Materials Research, Tohoku University
2019
University of Crete
2014
FORTH Institute of Electronic Structure and Laser
2014
Alexander Technological Educational Institute of Thessaloniki
2007-2013
Université Claude Bernard Lyon 1
2012
Laboratoire de Spectrométrie Ionique et Moléculaire
2012
Centre National de la Recherche Scientifique
2012
Abstract This work is a comparative study of four different techniques to determine the crystallinity high-density polyethylene (HDPE) nanocomposites filled with diameter sizes (5, 15 and 25 μm) graphene nanoplatelets (GNPs) at various amounts (0.5–5 wt%). The structure HDPE/GNPs was extensively studied by using experimental methods, such as X-ray diffraction, photoelectron spectroscopy, Fourier transform infrared Raman spectroscopy. To further provide complete comparison, differential...
The pressure evolution of the Raman spectrum graphene grown by chemical vapor deposition on polycrystalline copper is investigated with use polar and nonpolar transmitting media (PTM). $G$ 2$D$ bands exhibit similar slopes for both PTM irrespective any unintentional initial doping and/or strain samples. Our analysis suggests that pressure-induced charge transfer effects are too small to influence response graphene; rather, it determined compressibility substrate interaction PTM. For PTM, a...
A series of CoFe2O4 nanoparticles were formed through a variant hydrothermal synthesis based on self-assembled oil–water system in autoclaves at 200 °C the presence octadecylamine and trivalent iron cobalt acetylacetonates. The variation water content, different valence precursors (Co(II) Co(III)) as well Fe:Co precursor ratios (2:1 1:1) studied. with size range 9–16 nm high crystallinity enhanced saturation magnetization (∼89 emu g–1) have been isolated characterized. Raman spectroscopy...
The pressure response of crystalline 9,9′-spirobifluorene up to 8 GPa was studied by means Raman spectroscopy using a diamond anvil cell as chamber. With increasing pressure, the observed peaks shifted higher frequencies, reflecting bond hardening upon volume reduction, which much more pronounced for initially weaker intermolecular interactions than stronger intramolecular covalent bonds. significant changes in spectrum and evolution frequencies at ~1.3 both signaled pressure-induced...
The pressure response of double-wall carbon nanotubes has been investigated by means Raman spectroscopy up to 10 GPa. intensity the radial breathing modes outer tubes decreases rapidly but remain observable 9 GPa, exhibiting a behavior similar (but less pronounced) that single-wall nanotubes, which undergo shape distortion at higher pressures. In addition, tangential band external broadens and in amplitude. corresponding features internal appear be considerably sensitive pressure. All...
Optical detection of an individual single nano-object on opaque substrate and direct determination its absorption cross section is demonstrated using reflective spatial modulation spectroscopy. This method applied to optical imaging investigation single-wall carbon nanotubes in the 1.6 nm diameter range silicon substrates, which are also individually characterized by atomic force microscopy, scanning electron situ micro-Raman Absorption sections order 10-17 cm2 per atom measured for...
The vibrational properties of the (Gd1−xYx)3Ga5O12 (0≤x≤1) mixed garnet crystals are investigated at normal conditions by Raman and reflectivity infrared (IR)-spectroscopy while end members series have been theoretically means a rigid ion model. IR experimental spectra were analyzed Kramers–Kronig relations Lorentz oscillator obtained results compared discussed in detail with theory, providing useful parameters for estimating understanding optical garnets. majority expected peaks is resolved...
The dielectric function, reflectivity and Raman spectra of several epitaxial transition metal nitride films (TiN, ZrN, NbN, TaN, MoN, WN) on MgO substrates are reported. Apart from WN, the studied exhibit a negative real part thus may sustain plasmonic resonances with varying quality factors at diverse spectral regions. Epitaxial TiN ZrN outperform rest nitrides in terms figures merit. colloidal nanoparticles water ethanol predicted to support localized surface plasmon 596 496 nm,...
Cu<sub>2</sub>O NPs of 30 nm with antifungal properties were functionalized 9 NiFe<sub>2</sub>O<sub>4</sub> MNPs to construct hetero-NCs for magnetomechanical stress induction in <italic>S. cerevisiae</italic>.
Precise structural information on the Mg1-xAlxB2 superconductors in vicinity of x 0.5 is derived from high-resolution synchrotron X-ray powder diffraction measurements. We find that a hexagonal superstructure, accompanied by doubling c-axis, ordering Mg and Al alternating layers, shift B layers towards ~0.1 A, formed. The unusually large width (001/2) superlattice peak implies presence microstrain broadening, arising anisotropic stacking and/or modulations within ab plane. ordered phase...
High pressure Raman experiments were performed on the model system of double-wall carbon nanotubes. Changes in resonance profile radial breathing modes provide a unique demonstration inner tubes' band gap reduction with pressure. The overall trend internal normalized mode coefficients vs frequency reveals size-dependent properties individual Moreover, their quasilinear grouping, attributed to inner-outer tube (intratube) coupling and its spacing dependence, manifests existence specific combinations.
The high-pressure Raman response of double-wall carbon nanotubes (DWCNTs) in the radial breathing mode (RBM) frequency region can be used for identification both inner and their respective outer tubes. A simple anharmonic model this system demonstrates that pressure tube a DWCNT is uniquely defined by inner-outer spacing. Consequently, plot normalized coefficients RBM frequencies as function ambient serves map which allows unknown DWCNTs. present experimental results form basis such plot.
Heteroepitaxial non-polar III-Nitride layers may exhibit extensive anisotropy in the surface morphology and epilayer microstructure along distinct in-plane directions. The structural anisotropy, evidenced by “M”-shape dependence of (112¯0) x-ray rocking curve widths on beam azimuth angle, was studied combining transmission electron microscopy observations, Raman spectroscopy, high resolution diffraction, atomic force a-plane GaN epilayers grown r-plane sapphire substrates plasma-assisted...
The behavior of the phonon modes tetragonal phase two-dimensional polymerized ${\mathrm{C}}_{60}$ has been studied as a function pressure, up to 27.5 GPa, at room temperature by means Raman spectroscopy. Gradual transformation material new was observed in pressure region 19.0--21.0 GPa. As result this dramatic changes spectrum have recorded. Namely, total number bands reduced and very strong peaks appeared. characteristics provide indication that fullerene molecular cage is retained...
Abstract The structural stability of polycrystalline BaMoO 4 under hydrostatic pressure has been investigated by means Raman spectroscopy up to 8 GPa. spectra reveal a induced phase transition at ∼5.8 Upon release the structure reverts its ambient scheelite (CaWO ) with no observable hysteresis. large number active modes high suggests either an increase size unit cell and/or non‐centrosymmetric leading activation ungerade structure. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)