Institute of Fundamental Technological Research
Polish Academy of Sciences

Partners

K.W. Marszałek

AGH University of Science and Technology (PL)

Recent publications
1.  Bucholc B., Kaszyca K., Śpiewak P., Marszałek K., Kruszewski M., Ciupiński Ł., Kowiorski K., Zybała R., Thermoelectric properties of bismuth-doped magnesium silicide obtained by the self-propagating high-temperature synthesis, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 0239-7528, DOI: 10.24425/bpasts.2022.141007, Vol.70(3), No.e141007, pp.1-7, 2022

Abstract:
Doping is one of the possible ways to significantly increase the thermoelectric properties of many different materials. It has been confirmed that by introducing bismuth atoms into Mg sites in the Mg2Si compound, it is possible to increase career concentration and intensify the effect of phonon scattering, which results in remarkable enhancement in the figure of merit (ZT) value. Magnesium silicide has gained scientists’ attention due to its nontoxicity, low density, and inexpensiveness. This paper reports on our latest attempt to employ ultrafast selfpropagating high-temperature synthesis (SHS) followed by the spark plasma sintering (SPS) as a synthesis process of doped Mg2Si. Materials with varied bismuth doping were fabricated and then thoroughly analyzed with the laser flash method (LFA), X-ray diffraction (XRD), scanning electron microscopy (SEM) with an integrated energy-dispersive spectrometer (EDS). For density measurement, the Archimedes method was used. The electrical conductivity was measured using a standard four-probe method. The Seebeck coefficient was calculated from measured Seebeck voltage in the sample subjected to a temperature gradient. The structural analyses showed the Mg2Si phase as dominant and Bi2Mg3 located at grain boundaries. Bismuth doping enhanced ZT for every dopant concentration. ZT = 0:44 and ZT=0.38 were obtained for 3wt% and 2wt% at 770 K, respectively.

Keywords:
thermoelectric materials, magnesium silicide, bismuth doping, SHS, spark plasma sintering

Affiliations:
Bucholc B. - IPPT PAN
Kaszyca K. - Lukasiewicz Institute of Microelectronics and Photonics (PL)
Śpiewak P. - other affiliation
Marszałek K. - AGH University of Science and Technology (PL)
Kruszewski M. - other affiliation
Ciupiński Ł. - Warsaw University of Technology (PL)
Kowiorski K. - other affiliation
Zybała R. - Warsaw University of Technology (PL)
2.  Świątek Z., Gradys A., Maj Ł., Morgiel J., Marszałek K.W., Mania R., Szlezynger M., XRD and TEM in situ Heating of Large Period Ni/Al Multilayer Coatings, ACTA PHYSICA POLONICA A, ISSN: 0587-4246, DOI: 10.12693/APhysPolA.130.880, Vol.130, No.4, pp.880-883, 2016

Abstract:
The Ni/Al multilayer coating of λ ≈100 nm was deposited onto (001)-oriented monocrystalline silicon substrate using double target magnetron sputtering system equipped with rotating sample holder. The thicknesses of alternating layers were adjusted in the way to preserve the chemical composition ratio close to 50%Al:50%Ni (at.%). The in situ X-ray diffraction and in situ transmission electron microscopy heating experiments were carried out at relatively low heating rates (20°C/min) in order to study the phase transformation sequence. The investigations revealed that the reaction between Ni and Al multilayers starts at ≈200°C with precipitation of Al₃Ni phase, while above 300°C dominates precipitation of Ni₃Al and NiAl intermetallic phases. Both the X-ray and electron diffractions acquired at 450°C confirmed presence of the Ni₃Al and NiAl intermetallics, but the former pointed at still lasting traces of Ni(Al) solid solution.

Keywords:
transmission electron microscopy, multilayers

Affiliations:
Świątek Z. - Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL)
Gradys A. - IPPT PAN
Maj Ł. - Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL)
Morgiel J. - Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL)
Marszałek K.W. - AGH University of Science and Technology (PL)
Mania R. - AGH University of Science and Technology (PL)
Szlezynger M. - Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL)

Conference abstracts
1.  Świątek Z., Gradys A., Morgiel J., Marszałek K.W., Mania R., Szlezynger M., Maj Ł., XRD in-situ heating of large period Ni/Al reactive multilayer, XXIII Conference on Applied Crystallography, 2015-09-20/09-24, Krynica Zdrój (PL), pp.23-26, 2015

Category A Plus

IPPT PAN

logo ippt            Pawińskiego 5B, 02-106 Warsaw
  +48 22 826 12 81 (central)
  +48 22 826 98 15
 

Find Us

mapka
© Institute of Fundamental Technological Research Polish Academy of Sciences 2024