Browsing by Subject "Powder X ray diffraction"

Article

Effect of Bi-doping and Mg-excess on the thermoelectric properties of Mg2Si materials

Ioannou, M.; Polymeris, G. S.; Hatzikraniotis, E.; Paraskevopoulos, K. M.; Kyratsi, Theodora (2014)

In this work, Bi-doped magnesium silicide compounds were prepared by applying a combination of both, short-time ball milling and heating treatment. The effect of Mg excess was also studied, aiming towards further improvement ...

Article

Effect of silicon nitride/oxide on the structure and the thermal conductivity of CoSi nanocomposites

Ioannou, M.; Delimitis, A.; Symeou, E.; Giapintzakis, John; Kyratsi, Theodora (2017)

In this work, the fabrication of nanocomposites with silicon nitride/oxide into the thermoelectric matrix of cobalt silicide is presented. The different concentrations of nano-Si3N4 were intentionally introduced by mechanical ...

Article

Fabrication of nanocrystalline Mg 2Si via ball milling process: Structural studies

Ioannou, M.; Hatzikraniotis, E.; Lioutas, C.; Hassapis, T.; Altantzis, T.; Paraskevopoulos, K. M.; Kyratsi, Theodora (2012)

In this work, nanocrystalline Mg 2Si material was fabricated via wet ball milling process using n-hexane as process control agent. Milling parameters, with emphasis on milling time and ball size, and conditions were studied ...

Article

Solid-state synthesis and thermoelectric properties of Sb-doped Mg 2Si materials

Ioannou, M.; Polymeris, G.; Hatzikraniotis, E.; Khan, A. U.; Paraskevopoulos, K. M.; Kyratsi, Theodora (2013)

Sb-doped magnesium silicide compounds have been prepared through ball milling and solid-state reaction. Materials produced were near-stoichiometric. The structural modifications have been studied with powder x-ray diffraction. ...

Article

Solid-state synthesis of Mg 2Si via short-duration ball-milling and low-temperature annealing

Ioannou, M.; Chrissafis, K.; Pavlidou, E.; Gascoin, F.; Kyratsi, Theodora (2013)

In this work, a short duration ball-milling of elemental Mg and Si followed by a thermal treatment is suggested in order to synthesize magnesium silicide via solid-state reaction. The formation of magnesium silicide was ...

Article

Structural Characterization and Thermoelectric Properties of Hot-Pressed CoSi Nanocomposites

Ioannou, M.; Symeou, E.; Giapintzakis, John; Kyratsi, Theodora (2014)

Fabrication of nanocomposites by introduction of SiO2 metal oxide nanoparticles into a cobalt silicide thermoelectric matrix is studied. The CoSi matrix material was prepared through solid-state synthesis, and the nano-SiO2 ...

Article

Structural features of ball-milled nanostructured K2Bi 8Se13 thermoelectric material

Lioutas, C. B.; Hatzikraniotis, E.; Ioannou, M.; Paraskevopoulos, K. M.; Kyratsi, Theodora (2011)

In this work, K2Bi8Se13 material was ball-milled in order to develop nanostructures through the modification of structural features. Structural changes during ball-milling were followed by powder X-ray diffraction measurements, ...