• Article  

      Crystal/glass phase change in KSb5S8 studied through thermal analysis techniques 

      Chrissafis, K.; Kyratsi, Theodora; Paraskevopoulos, K. M.; Kanatzidis, M. G. (2004)
      The reversible crystal-glass and glass-crystal transitions discovered in KSb5S8 were studied in detail with nonisothermal scanning calorimetry techniques. When cooled, molten KSb5S8 becomes a metastable glass, which can ...
    • 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  

      KSb5S8: A wide bandgap phase-change material for ultra high density rewritable information storage 

      Kyratsi, Theodora; Chrissafis, K.; Wachter, J.; Paraskevopoulos, K. M.; Kanatzidis, M. G. (2003)
      The reversible glassformation and glass crystallization properties of KSb3S8 was described. On the basis of glass transition and crystallization kinetics of KSb5S8, it was found that the crystallization rate and assoicated ...
    • Article  

      Local structure and influence of bonding on the phase-change behavior of the chalcogenide compounds K1-xRbxSb5S8 

      Wachter, J. B.; Chrissafis, K.; Petkov, V.; Malliakas, C. D.; Bilc, D. I.; Kyratsi, Theodora; Paraskevopoulos, K. M.; Mahanti, S. D.; Torbrügge, T.; Eckert, H.; Kanatzidis, M. G. (2007)
      KSb5S8 and its solid solution analogs with Rb and Tl were found to exhibit a reversible and tunable glass→crystal→glass phase transition. Selected members of this series were analyzed by differential scanning calorimetry ...
    • 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 inhomogeneities, shallow defects, and charge transport in the series of thermoelectric materials K2Bi8-xSb xSe13 

      Kyratsi, Theodora; Hatzikraniotis, E.; Paraskevopoulos, K. M.; Malliakas, C. D.; Dyck, J. S.; Uher, C.; Kanatzidis, M. G. (2006)
      The charge transport properties of the low-dimensional thermoelectric materials K2 Bi8-x Sbx Se13 (0<x≤8) were studied as a function of temperature and composition. The Seebeck coefficient shows an evolution from n - to p ...
    • Conference Object  

      Synthesis, crystal structure and thermoelectric properties of β-K 2Bi 8Se 13 solid solutions 

      Kyratsi, Theodora; Chung, D. Y.; Dyck, J. S.; Uher, C.; Lal, S.; Loo, S.; Hogan, T.; Ireland, J.; Kannewurf, C. R.; Hatzikraniotis, E.; Paraskevopoulos, K. M.; Kanatzidis, M. G. (Affiliation: Department of Chemistry, Michigan State University, East Lansing, MI 48824, United StatesAffiliation: Department of Physics, University of Michigan, Ann Arbor, MI 48109, United StatesAffiliation: Department of Electrical Engineering, Michigan State University, East Lansing, MI 48824, United StatesAffiliation: Department of Electrical Engineering, Northwestern University, Evanston, IL 60208, United StatesAffiliation: Department of Physics, Aristotle University of Thessaloniki, 54006 Thessaloniki, GreeceCorrespondence Address: Kyratsi, T.Department of Chemistry, Michigan State University, East Lansing, MI 48824, United States, 2003)
      Solid solution series of the type K 2Bi 8-xSb xSe 13, K 2-xRb xBi 8Se 13 as well as K 2B 18Se 13-xS x were prepared and the distribution of the atoms (Bi/Sb, K/Rb and Se/S) on different crystallographic sites, the band ...
    • Conference Object  

      Thermoelectric properties of K 2Bi 8Se 13-xS x solid solutions 

      Kyratsi, Theodora; Lal, S.; Hogan, T.; Kanatzidis, M. G. (Affiliation: Department of Chemistry, Michigan State University, East Lansing, MI 48824, United StatesAffiliation: Department of Mechanical and Manufacturing Engineering, School of Engineering, University of Cyprus, Nicosia, CyprusAffiliation: Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48824, United StatesCorrespondence Address: Kyratsi, T.Department of Chemistry, Michigan State University, East Lansing, MI 48824, United States, 2006)
      Derivatives of β-K 2Bi 8Se 13 are an interesting series of materials for thermoelectric investigations due to their very low thermal conductivity and highly anisotropic electrical properties. Up to now substitutions on the ...
    • Conference Object  

      Thermoelectric properties of K2Bi8-xSbxSe13 solid solutions and Se doping 

      Kyratsi, Theodora; Dyck, J. S.; Chen, W.; Chung, D. Y.; Uher, C.; Paraskevopoulos, K. M.; Kanatzidis, M. G. (Affiliation: Department of Chemistry, Michigan State University, East Lansing, MI 48824, United StatesCorrespondence Address: Kyratsi, T.Department of Chemistry, Michigan State University, East Lansing, MI 48824, United States, 2002)
      Our efforts to improve the thermoelectric properties of β-K2Bi8Se13, led to systematic studies of solid solutions of the type β-K2Bi8-xSbxSe13. The charge transport properties and thermal conductivities were studied for ...
    • Conference Object  

      Transport properties of the doped thermoelectric material K2Bi8-xSbxSe13 

      Brazis, P. W.; Ireland, J. R.; Lane, M. A.; Kyratsi, Theodora; Chung, D. Y.; Kanatzidis, M. G.; Kannewurf, C. R. (Affiliation: Dept. of Electrical and Comp. Eng., Northwestern University, Evanston, IL 60208-3118, United StatesCorrespondence Address: Brazis, P.W.Dept. of Electrical and Comp. Eng., Northwestern University, Evanston, IL 60208-3118, United States, 2001)
      The synthesis, physicochemical, spectroscopic, and structural characterization of the compound β-K2Bi8Se13 has been previously reported. The results indicated that this material should be investigated further for possible ...