Browsing by Subject "Crystal structure"

Article

Ab-initio electronic structure calculations and properties of [SixSn1 − x]3N4 ternary nitrides

Pavloudis, T.; Zervos, Matthew; Komninou, P.; Kioseoglou, J. (2016)

We carry out ab initio electronic structure calculations of (SixSn1 − x)3N4 using density functional theory with projector augmented-wave potentials under the generalized gradient approximation. We find that the energetically ...

Article

Bi/Sb distribution and its consequences in solid solution members of the thermoelectric materials K2Bi8-xSbxSe13

Kyratsi, Theodora; Chung, D. Y.; Kanatzidis, M. G. (2002)

In an effort to understand the nature of mass fluctuations introduced when β-K2Bi8Se13 is alloyed with K2Sb8Se13 we determined the detailed crystal structures of two solid solutions of the type K2Bi8-xSbxSe13 with x=4.0 ...

Article

Core-shell PbS/Sn:In2O3 and branched PbIn2S4/Sn:In2O3 nanowires in quantum dot sensitized solar cells

Zervos, Matthew; Vasile, E.; Vasile, E.; Othonos, A. (2017)

Core-shell PbS/Sn:In2O3 and branched PbIn2S4/Sn:In2O3 nanowires have been obtained via the deposition of Pb over Sn:In2O3 nanowires and post growth processing under H2S between 100 C-200 C and 300 C-500 C respectively. The ...

Article

Data storage applications based on LiCoO2 thin films grown on Al2O3 and Si substrates

Svoukis, E.; Mihailescu, C. N.; Mai, V. H.; Schneegans, O.; Breza, K.; Lioutas, C.; Giapintzakis, John (2015)

In this study, LiCoO2 thin films were investigated for data storage applications based on scanning probe mediated approaches. LiCoO2, compared to other materials proposed for scanning probe mediated nanoscale patterning, ...

Article

Gallium hydride vapor phase epitaxy of GaN nanowires

Zervos, Matthew; Othonos, A. (2011)

Straight GaN nanowires (NWs) with diameters of 50 nm, lengths up to 10 μm and a hexagonal wurtzite crystal structure have been grown at 900°C on 0.5 nm Au/Si(001) via the reaction of Ga with NH3 and N2:H2, where the H2 ...

Conference Object

Initial assessment of the thermoelectric properties for the mixed system K2-xRbxBi8Se13

Ireland, J. R.; Kyratsi, Theodora; Kanatzidis, M. G.; Kannewurf, C. R. (Affiliation: Dept. of Elec. and Comp. Engineering, Northwestern University, Evanston, IL 60208-3118, United StatesCorrespondence Address: Ireland, J.R.Dept. of Elec. and Comp. Engineering, Northwestern University, Evanston, IL 60208-3118, United States, 2002)

In previous studies we have investigated the thermoelectric properties of undoped and doped compositions of β-K2Bi8Se13. The attempt to substitute Rb for K resulted in a different structure type, but with potentially useful ...

Article

An investigation into the conversion of In2O3 into InN nanowires

Papageorgiou, P.; Zervos, Matthew; Othonos, A. (2011)

Straight In2O3 nanowires (NWs) with diameters of 50 nm and lengths ≥2 μm have been grown on Si(001) via the wet oxidation of In at 850°C using Au as a catalyst. These exhibited clear peaks in the X-ray diffraction corresponding ...

Article

La0.95Sr0.05Coo3: An efficient room-temperature thermoelectric oxide

Andrbulakis, J.; Migiakis, P.; Giapintzakis, John (2004)

Electric resistivity, thermal conductivity, and the thermopower of polycrystalline Sr-doped LaCoO3 with composition La 0.9Sr0.5CoO3 were measured. The crystal structure of the synthesized powders was determined by x-ray ...

Article

Layered atomic structures of double oxides for low shear strength at high temperatures

Stone, D.; Liu, J.; Singh, D. P.; Muratore, C.; Voevodin, A. A.; Mishra, S.; Rebholz, Claus; Ge, Q.; Aouadi, S. M. (2010)

Double oxide phases combining a transition metal and a noble metal have recently become a subject of investigation as solid lubricant materials for high-temperature tribological applications. Here, we study the changes in ...

Article

Magnetic properties of Fe3O4 thin films grown on different substrates by laser ablation

Paramês, M. L.; Viskadourakis, Z.; Rogalski, M. S.; Mariano, J.; Popovici, N.; Giapintzakis, John; Conde, O. (2007)

Magnetite thin films have been grown onto (1 0 0)Si, (1 0 0)GaAs and (0 0 0 1)Al2O3, at substrate temperatures varying from 473 to 673 K, by UV pulsed laser ablation of Fe3O4 targets in reactive atmospheres of O2 and Ar, ...

Article

Modification of thermoelectric properties using insertion techniques

Hatzikraniotis, E.; Kyratsi, Theodora; Chrissafis, K.; Paraskevopoulos, K. M. (1999)

In this work is presented the application insertion techniques for the modification of the performance of thermoelectric materials. The results indicate that in cases as in Bi2Se3 compounds where insertion of foreign species ...

Article

The nitridation of ZnO nanowires

Zervos, Matthew; Karipi, C.; Othonos, A. (2012)

ZnO nanowires (NWs) with diameters of 50 to 250 nm and lengths of several micrometres have been grown by reactive vapour transport via the reaction of Zn with oxygen on 1 nm Au/Si(001) at 550°C under an inert flow of Ar. ...

Article

Novel combustion synthesis of carbon foam‑aluminum fluoride nanocomposite materials

Kostoglou, N.; Gunduz, I. Emre; Isik, T.; Ortalan, V.; Constantinides, G.; Kontos, A. G.; Steriotis, T.; Ryzhkov, V.; Bousser, E.; Matthews, A.; Doumanidis, C. C.; Mitterer, C.; Rebholz, Claus (2018)

The facile, rapid and bulk production of composite materials consisting of carbon nanostructures doped with metal-based compounds has been a significant challenge for various research areas where such types of materials ...

Article

Pb doping of In2O3 and their conversion to highly conductive PbS/In2S3-3xO3x nanowires with infra red emission

Zervos, Matthew; Othonos, A.; Gianetta, V.; Nassiopoulou, A. G. (2016)

We have grown Pb doped In2O3 nanowires at 800°C which have the cubic bixbyite crystal structure of In2O3 and contain orthorhombic α-PbO. These had resistances up to ≈10 Ω and exhibited photoluminescence at 2.5 eV but we ...

Article

Relations of crystal structure to magnetic properties in the quasi-one-dimensional compound PbNi1.88Mg0.12V 2O8

Mastoraki, I.; Lappas, A.; Giapintzakis, John; Többens, D.; Hernández-Velasco, J. (2004)

The crystal structure of the quasi-one-dimensional oxide PbNi 1.88Mg0.12V2O8 has been studied by Rietveld analysis of combined high-resolution neutron and X-ray powder diffraction data at 300K and at low temperatures. The ...

Article

Sn doped β-Ga2O3 and β-Ga2S3 nanowires with red emission for solar energy spectral shifting

Zervos, Matthew; Othonos, A.; Gianneta, V.; Travlos, A.; Nassiopoulou, A. G. (2015)

Sn doped β-Ga2O3 nanowires have been grown on Si(001) via the vapor-liquid-solid mechanism at 800 °C over a broad range of compositions. These have a monoclinic β-Ga2O3 crystal structure and minimum resistances for 1-2 at. ...

Article

Sn:In2O3 and Sn:In2O3/NiS2 Core-Shell Nanowires on Ni, Mo Foils and C Fibers for H2 and O2 Generation

Zervos, Matthew; Leontidis, E.; Tanasǎ, E.; Vasile, E.; Othonos, A. (2017)

Sn:In2O3 nanowires have been grown by the vapor liquid solid mechanism on Si, Ni, Mo, and C fibers. These were used to obtain Sn:In2O3/NiS2 core-shell nanowires by the deposition of 10 nm Ni over the Sn:In2O3 nanowires ...

Article

Structure, reactivity, luminescence and magnetism of dinuclear Ln 3+ complexes produced by the Ln3+-assisted hydrolysis of 3,6-bis(2-pyridyl)tetrazine

Panayiotidou, L.; Drouza, C.; Arabatzis, N.; Lianos, P.; Stathatos, E.; Viskadourakis, Z.; Giapintzakis, John; Keramidas, A. D. (2013)

Twelve Pr3+, Sm3+, Eu3+, Gd3+, Tb3+ and Dy3+ complexes of N-(pyridin-2-ylmethylene) picolinohydrazonate (phzp-) were synthesized by the Ln3+ assisted hydrolysis of 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine. Crystallographic ...

Article

Sulfur doping of M/In2O3 (M=Al,W) nanowires with room temperature near infra red emission

Zervos, Matthew; Mihailescu, C.; Giapintzakis, John; Othonos, A.; Travlos, A. (2015)

We have investigated the growth of Al doped In2O3 nanowires via the vapor-liquid-solid mechanism at 800°C using Au as a catalyst. We find that the Al is not incorporated into the cubic bixbyite crystal structure of In2O3 ...

Article

Syntheses, crystal Structures and electronic Structures of new metal chalcoiodides Bi2CuSe3I and Bi6Cu3S10I

Liang, I.-C.; Bilc, D. I.; Manoli, M.; Chang, W.-Y.; Lin, W.-F.; Kyratsi, Theodora; Hsu, K. F. (2016)

Two new metal chalcoiodides were synthesized by solid-state reactions at 400 °C. Crystal Data: Bi2CuSe3I, 1, monoclinic, C2/m, a=14.243(2) Å, b=4.1937(7) Å, c=14.647(2) Å, β=116.095(2)°, V=785.7(2) Å3, and Z=4