Browsing by Subject "Tin"

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

Carrier relaxation dynamics in SnxNy nanowires grown by chemical vapor deposition

Othonos, A.; Zervos, Matthew (2009)

Carrier relaxation dynamics in tin nitride (SnxNy) nanowires have been investigated using femtosecond transient absorption spectroscopy. The nanowires were grown directly on quartz using chemical vapor deposition and had ...

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

Current Transport Properties of CuS/Sn:In2O3 versus CuS/SnO2 Nanowires and Negative Differential Resistance in Quantum Dot Sensitized Solar Cells

Zervos, Matthew; Vasile, E.; Karageorgou, E.; Othonos, A. (2016)

The structural, optical, and electrical transport properties of nanowires obtained by the deposition of Cu over Sn doped In2O3 and SnO2 nanowires followed by processing under H2S between 100 and 500°C have been investigated ...

Article

Effect of antimony-doping and germanium on the highly efficient thermoelectric Si-rich-Mg2(Si,Sn,Ge) materials

Vlachos, N.; Polymeris, G. S.; Manoli, M.; Hatzikraniotis, E.; Khan, A. U.; Lioutas, C. B.; Stefanaki, E. C.; Pavlidou, E.; Paraskevopoulos, K. M.; Giapintzakis, John; Kyratsi, Theodora (2017)

Two series of materials (a) Mg2Si0.55-ySn0.4Ge0.05Sby, 0 ≤ y ≤ 0.0175 and (b) Mg2Si0.5875-xSn0.4GexSb0.0125, 0 ≤ x ≤ 0.20 have been developed and studied in terms of structural features and thermoelectric properties/performance. ...

Article

Electrical, structural, and optical properties of sulfurized Sn-doped In2O3 nanowires

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

Sn-doped In2O3 nanowires have been grown on Si via the vapor-liquid-solid mechanism at 800 °C and then exposed to H2S between 300 to 600 °C. We observe the existence of cubic bixbyite In2O3 and hexagonal SnS2 after processing ...

Article

Electronic Structure and Thermoelectric Properties of Pseudoquaternary Mg2Si1-x-ySnxGey-Based Materials

Kutorasinski, K.; Tobola, J.; Kaprzyk, S.; Khan, A. U.; Kyratsi, Theodora (2014)

A theoretical study is presented on complex pseudoternary Bi-doped Mg2Si1-x-ySnxGey materials, which have recently been revealed to reach high thermoelectric figures of merit (ZT) of ∼1.4. Morphological characterization ...

Article

Enhanced growth and photoluminescence properties of SnxN y (x>y) nanowires grown by halide chemical vapor deposition

Zervos, Matthew; Othonos, A. (2011)

Tin nitride nanowires have been grown by halide chemical vapor deposition via the reaction of Sn with NH4Cl at 425 °C under a steady flow of NH3 using small ramp rates y) with a hexagonal structure, i.e. c=5.193 , a=3.725 ...

Article

High thermoelectric figure of merit of Mg2Si 0.55Sn0.4Ge0.05 materials doped with Bi and Sb

Khan, A. U.; Vlachos, N.; Kyratsi, Theodora (2013)

Thermoelectric properties of new Bi- and Sb-doped Mg2Si 0.55Sn0.4Ge0.05 compounds prepared by powder methods were studied in the temperature range 300-823 K. The materials exhibited compositional inhomogeneites consisting ...

Conference Object

Modeling of thermal conductivity in high performing thermoelectric materials

Hatzikraniotis, E.; Kyratsi, Theodora; Paraskevopoulos, K. M. (Institute of Physics Publishing, 2017)

The enhanced TE-performance in Mg2Si-Mg2Sn based pseudo-binaries is presented, which is attributed to low thermal conductivity. Sn-Si alloying, reduces the lattice thermal conductivity due to mass fluctuation. Furthermore, ...

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

Structural properties of SnO2 nanowires and the effect of donor like defects on its charge distribution

Zervos, Matthew; Othonos, A.; Tsokkou, D.; Kioseoglou, J.; Pavlidou, E.; Komninou, P. (2013)

Tin oxide (SnO2) nanowires (NWs) with diameters of 50 nm, lengths up to 100 μm and a tetragonal rutile crystal structure have been grown by low pressure reactive vapour transport on 1 nm Au/Si(001). The free carrier density ...

Article

Surface passivation and conversion of SnO2 to SnS2 nanowires

Zervos, Matthew; Mihailescu, C. N.; Giapintzakis, John; Othonos, A.; Luculescu, C. R. (2015)

SnO2 nanowires have been grown on Si(0 0 1) via the vapour-liquid-solid mechanism at 800 °C and then exposed to H2S between 300 and 600 °C. The SnS2/SnO2 nanowires obtained at 300 °C consist of tetragonal rutile SnO2 and ...

Article

Synthesis of Tin nitride Sn xN y nanowires by chemical vapour deposition

Zervos, Matthew; Othonos, A. (2009)

Tin nitride (Sn xN y) nanowires have been grown for the first time by chemical vapour deposition on n-type Si(111) and in particular by nitridation of Sn containing NH 4Cl at 450 °C under a steady flow of NH 3. The Sn xN ...

Article

A systematic study of the nitridation of SnO 2 nanowires grown by the vapor liquid solid mechanism

Zervos, Matthew; Othonos, A. (2012)

SnO 2 nanowires (NWs) with diameters of 50 nm and lengths ≥10 μm have been grown at 800 °C on 1.0 nm Au/Si(001) via the vapor liquid solid mechanism and the low pressure chemical vapor deposition. These exhibited clear ...

Article

Tin oxide nanowires: The influence of trap states on ultrafast carrier relaxation

Othonos, A.; Zervos, Matthew; Tsokkou, D. (2009)

We have studied the optical properties and carrier dynamics in SnO 2 nanowires (NWs) with an average radius of 50 nm that were grown via the vapor-liquid solid method. Transient differential absorption measurements have ...