51
|
Likhanov MS, Verchenko VY, Bykov MA, Tsirlin AA, Gippius AA, Berthebaud D, Maignan A, Shevelkov AV. Crystal growth, electronic structure, and properties of Ni-substituted FeGa. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2015.08.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
52
|
Nasonova DI, Presniakov IA, Sobolev AV, Verchenko VY, Tsirlin AA, Wei Z, Dikarev EV, Shevelkov AV. Role of iron in synthetic tetrahedrites revisited. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2015.12.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
53
|
Yashina LV, Volykhov AA, Neudachina VS, Aleksandrova NV, Reshetova LN, Tamm ME, Pérez-Dieste V, Escudero C, Vyalikh DV, Shevelkov AV. Experimental and Computational Insight into the Chemical Bonding and Electronic Structure of Clathrate Compounds in the Sn-In-As-I System. Inorg Chem 2015; 54:11542-9. [PMID: 26574775 DOI: 10.1021/acs.inorgchem.5b02223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inorganic clathrate materials are of great fundamental interest and potential practical use for application as thermoelectric materials in freon-free refrigerators, waste-heat converters, direct solar thermal energy converters, and many others. Experimental studies of their electronic structure and bonding have been, however, strongly restricted by (i) the crystal size and (ii) essential difficulties linked with the clean surface preparation. Overcoming these handicaps, we present for the first time a comprehensive picture of the electronic band structure and the chemical bonding for the Sn(24-x-δ)InxAs(22-y)I8 clathrates obtained by means of photoelectron spectroscopy and complementary quantum modeling.
Collapse
|
54
|
Verchenko VY, Tsirlin AA, Sobolev AV, Presniakov IA, Shevelkov AV. Ferromagnetic Order, Strong Magnetocrystalline Anisotropy, and Magnetocaloric Effect in the Layered Telluride Fe3−δGeTe2. Inorg Chem 2015; 54:8598-607. [DOI: 10.1021/acs.inorgchem.5b01260] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
55
|
Charkin DO, Demchyna R, Prots Y, Borrmann H, Burkhardt U, Schwarz U, Schnelle W, Plokhikh IV, Kazakov SM, Abakumov AM, Batuk D, Verchenko VY, Tsirlin AA, Curfs C, Grin Y, Shevelkov AV. Two New Arsenides, Eu7Cu44As23 and Sr7Cu44As23, With a New Filled Variety of the BaHg11 Structure. Inorg Chem 2014; 53:11173-84. [PMID: 25265469 DOI: 10.1021/ic5017615] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
56
|
Roslova MV, Lebedev OI, Morozov IV, Aswartham S, Wurmehl S, Büchner B, Shevelkov AV. Diversity of microstructural phenomena in superconducting and non-superconducting Rb(x)Fe(2-y)Se2: a transmission electron microscopy study at the atomic scale. Inorg Chem 2013; 52:14419-27. [PMID: 24283501 DOI: 10.1021/ic402710r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Superconducting (SC) and non-superconducting (non-SC)Rb(x)Fe(2-y)Se2 crystals were grown using the "self-flux" technique in order to assign the microstructural changes to the onset of superconductivity in complex iron selenides. The crystals were thoroughly characterized by magnetic susceptibility and transport measurements as well as powder X-ray diffraction. Special attention was paid to the comparison of the microstructure of the crystals with and without the superconducting transition by means of transmission electron microscopy (TEM). It is shown that the alternation of ordered and disordered regions on the sample surface and along the c-axis is characteristic for both SC and non-SC materials and therefore does not necessarily represent a trigger of superconductivity. Three types of electron diffraction patterns were found for the superconducting Rb(x)Fe(2-y)Se2 sample, of which one is observed for the first time and originates from alkali metal ordering. Moreover, for the superconducting Rb(x)Fe(2-y)Se2 material a monoclinic distortion with β ∼ 87° was observed, leading to the space group I2/m. This monoclinic distortion seems to be an attribute of the superconducting material only, whereas in the non-superconducting sample the orthogonality of the crystallographic axes is preserved.
Collapse
|
57
|
Schnurr S, Wiedwald U, Ziemann P, Verchenko VY, Shevelkov AV. Structural and thermoelectric properties of TMGa3 (TM = Fe, Co) thin films. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2013; 4:461-466. [PMID: 23946915 PMCID: PMC3740773 DOI: 10.3762/bjnano.4.54] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/16/2013] [Indexed: 06/02/2023]
Abstract
Based on chemically synthesized powders of FeGa3, CoGa3, as well as of a Fe0.75Co0.25Ga3 solid solution, thin films (typical thickness 40 nm) were fabricated by flash evaporation onto various substrates held at ambient temperature. In this way, the chemical composition of the powders could be transferred one-to-one to the films as demonstrated by Rutherford backscattering experiments. The relatively low deposition temperature necessary for conserving the composition leads, however, to 'X-ray amorphous' film structures with immediate consequences on their transport properties: A practically temperature-independent electrical resistivity of ρ = 200 μΩ·cm for CoGa3 and an electrical resistivity of about 600 μΩ·cm with a small negative temperature dependence for FeGa3. The observed values and temperature dependencies are typical of high-resistivity metallic glasses. This is especially surprising in the case of FeGa3, which as crystalline bulk material exhibits a semiconducting behavior, though with a small gap of 0.3 eV. Also the thermoelectric performance complies with that of metallic glasses: Small negative Seebeck coefficients of the order of -6 μV/K at 300 K with almost linear temperature dependence in the range 10 K ≤ T ≤ 300 K.
Collapse
|
58
|
Verchenko VY, Vasiliev AS, Tsirlin AA, Kulbachinskii VA, Kytin VG, Shevelkov AV. Synthesis and thermoelectric properties of Re3As6.6In0.4 with Ir3Ge7 crystal structure. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2013; 4:446-452. [PMID: 23946913 PMCID: PMC3740774 DOI: 10.3762/bjnano.4.52] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 06/12/2013] [Indexed: 06/02/2023]
Abstract
The Re3As7- x In x solid solution was prepared for x ≤ 0.5 by heating the elements in stoichiometric ratios in evacuated silica tubes at 1073 K. It crystallizes with the Ir3Ge7 crystal structure, space group Im-3m, with a unit-cell parameter a ranging from 8.716 to 8.747 Å. The crystal structure and properties were investigated for a composition with x = 0.4. It is shown that indium substitutes arsenic exclusively at one crystallographic site, such that the As-As dumbbells with d As-As = 2.54 Å remain intact. Re3As6.6In0.4 behaves as a bad metal or heavily doped semiconductor, with electrons being the dominant charge carriers. It possesses high values of Seebeck coefficient and low thermal conductivity, but relatively low electrical conductivity, which leads to rather low values of the thermoelectric figure of merit.
Collapse
|
59
|
Kirsanova MA, Mori T, Maruyama S, Abakumov AM, Tendeloo GV, Olenev A, Shevelkov AV. Cationic Clathrate of Type-III Ge172–xPxTey (y ≈ 21.5, x ≈ 2y): Synthesis, Crystal Structure and Thermoelectric Properties. Inorg Chem 2013; 52:8272-9. [DOI: 10.1021/ic401203r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
60
|
Kirsanova MA, Shevelkov AV. Clathrates and semiclathrates of Type-I: crystal structure and superstructures. Z KRIST-CRYST MATER 2013. [DOI: 10.1524/zkri.2013.1608] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The review surveys the crystal chemistry of inorganic compounds belonging to the structure type of clathrate-I. The compounds of this family exhibit an unexpected variety of both chemical composition and features of the crystal structure. The basic crystal structure of clathrate-I and different variants of its modification, such as siting, position splitting, and superstructure formation including transformation to semiclathrates, are considered in terms of the group-subgroup relationship.
Collapse
|
61
|
Kirsanova MA, Mori T, Maruyama S, Matveeva M, Batuk D, Abakumov AM, Gerasimenko AV, Olenev AV, Grin Y, Shevelkov AV. Synthesis, Structure, and Transport Properties of Type-I Derived Clathrate Ge46–xPxSe8–y (x = 15.4(1); y = 0–2.65) with Diverse Host–Guest Bonding. Inorg Chem 2012; 52:577-88. [DOI: 10.1021/ic3011025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
62
|
Abramchuk NS, Carrillo-Cabrera W, Veremchuk I, Oeschler N, Olenev AV, Prots Y, Burkhardt U, Dikarev EV, Grin J, Shevelkov AV. Homo- and heterovalent substitutions in the new clathrates I Si30P16Te(8-x)Se(x) and Si(30+x)P(16-x)Te(8-x)Br(x): synthesis, crystal structure, and thermoelectric properties. Inorg Chem 2012; 51:11396-405. [PMID: 23072375 DOI: 10.1021/ic3010097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The new cationic clathrates I Si(30)P(16)Te(8-x)Se(x) and Si(30+x)P(16-x)Te(8-x)Br(x) were synthesized by the standard ampule technique. The Si(30)P(16)Te(8-x)Se(x) (x = 0-2.3) clathrates crystallize in the cubic space group Pm3̅n with the unit cell parameter a ranging from 9.9382(2) to 9.9696(1) Å. In the case of the Si(30+x)P(16-x)Te(8-x)Br(x) (x = 1-6.4) clathrates, the lattice parameter varies from 9.9720(8) to 10.0405(1) Å; at lower Si/P ratios (x = 1-3) the ordering of bromine atoms induces the splitting of the guest positions and causes the transformation from the space group Pm3n to Pm3. Irrespective of the structure peculiarities, the normal temperature motion of the guest atoms inside the oversized cages of the framework is observed. The title clathrates possess very low thermal expansion coefficients ranging from 6.6 × 10(-6) to 1.0 × 10(-5) K(-1) in the temperature range of 298-1100 K. The characteristic Debye temperature is about 490 K. Measurements of the electrical resistivity and thermopower showed typical behavior of p-type thermally activated semiconductors, whereas the temperature behavior of the thermal conductivity is glasslike and in general consistent with the PGEC concept. The highest value of the thermoelectric figure of merit (ZT = 0.1) was achieved for the Br-bearing clathrate Si(32.1(2))P(13.9(2))Te(6.6(2))Br(1.0(1)) at 750 K.
Collapse
|
63
|
Kulbachinskii VA, Kytin VG, Kudryashov AA, Kuznetsov AN, Shevelkov AV. On the electronic structure and thermoelectric properties of BiTeBr and BiTeI single crystals and of BiTeI with the addition of BiI3 and CuI. J SOLID STATE CHEM 2012. [DOI: 10.1016/j.jssc.2012.05.037] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
64
|
Kelm EA, Olenev AV, Bykov MA, Sobolev AV, Presniakov IA, Kulbachinskii VA, Kytin VG, Shevelkov AV. Synthesis, Crystal Structure, and Thermoelectric Properties of Clathrates in the Sn-In-As-I System. Z Anorg Allg Chem 2011. [DOI: 10.1002/zaac.201100287] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
65
|
Kovnir K, Stockert U, Budnyk S, Prots Y, Baitinger M, Paschen S, Shevelkov AV, Grin Y. Introducing a Magnetic Guest to a Tetrel-Free Clathrate: Synthesis, Structure, and Properties of EuxBa8–xCu16P30 (0 ≤ x ≤ 1.5). Inorg Chem 2011; 50:10387-96. [DOI: 10.1021/ic201474h] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
66
|
Kirsanova MA, Reshetova LN, Olenev AV, Abakumov AM, Shevelkov AV. Semiclathrates of the Ge-P-Te System: Synthesis and Crystal Structures. Chemistry 2011; 17:5719-26. [DOI: 10.1002/chem.201003553] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 02/01/2011] [Indexed: 11/08/2022]
|
67
|
Kirsanova MA, Olenev AV, Abakumov AM, Bykov MA, Shevelkov AV. Extension of the Clathrate Family: The Type X Clathrate Ge79P29S18Te6. Angew Chem Int Ed Engl 2011; 50:2371-4. [DOI: 10.1002/anie.201007483] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Indexed: 11/09/2022]
|
68
|
Kirsanova MA, Olenev AV, Abakumov AM, Bykov MA, Shevelkov AV. Extension of the Clathrate Family: The Type X Clathrate Ge79P29S18Te6. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201007483] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
69
|
Zaikina JV, Mori T, Kovnir K, Teschner D, Senyshyn A, Schwarz U, Grin Y, Shevelkov AV. Inside Cover: Bulk and Surface Structure and High‐Temperature Thermoelectric Properties of Inverse Clathrate‐III in the Si‐P‐Te System (Chem. Eur. J. 42/2010). Chemistry 2010. [DOI: 10.1002/chem.201090208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
70
|
Zaikina JV, Mori T, Kovnir K, Teschner D, Senyshyn A, Schwarz U, Grin Y, Shevelkov AV. Bulk and Surface Structure and High‐Temperature Thermoelectric Properties of Inverse Clathrate‐III in the Si‐P‐Te System. Chemistry 2010; 16:12582-9. [PMID: 20945448 DOI: 10.1002/chem.201001990] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
71
|
|
72
|
Zaikina JV, Kovnir KA, Burkhardt U, Schnelle W, Haarmann F, Schwarz U, Grin Y, Shevelkov AV. Cationic clathrate I Si(46-x)P(x)Te(y) (6.6(1) < or = y < or = 7.5(1), x < or = 2y): crystal structure, homogeneity range, and physical properties. Inorg Chem 2009; 48:3720-30. [PMID: 19281208 DOI: 10.1021/ic8023887] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new cationic clathrate I Si(46-x)P(x)Te(y) (6.6(1) < or = y < or = 7.5(1), x < or = 2y at 1375 K) was synthesized from the elements and characterized by X-ray powder diffraction, thermal analysis, scanning electron microscopy, wavelength dispersive X-ray spectroscopy (WDXS), neutron powder diffraction, and (31)P NMR spectroscopy. The thermal behaviors of the magnetic susceptibility and resistivity were investigated as well. Si(46-x)P(x)Te(y) reveals a wide homogeneity range due to the presence of vacancies in the tellurium guest positions inside the smaller cage of the clathrate I structure. The vacancy ordering in the structure of Si(46-x)P(x)Te(y) causes the change of space group from Pm3n (ideal clathrate I) to Pm3 accompanied by the redistribution of P and Si atoms over different framework positions. Neutron powder diffraction confirmed that P atoms preferably form a cage around the vacancy-containing tellurium guest position. Additionally, (31)P NMR spin-spin relaxation experiments revealed the presence of sites with different coordination of phosphorus atoms. Precise determination of the composition of Si(46-x)P(x)Te(y) by WDXS showed slight but noticeable deviation (x < or = 2y) of phosphorus content from the Zintl counting scheme (x = 2y). The compound is diamagnetic while resistivity measurements show activated behavior or that of heavily doped semiconductors. Thermal analysis revealed high stability of the investigated clathrate: Si(46-x)P(x)Te(y) melts incongruently at approximately 1460 K in vacuum and is stable in air against oxidation up to 1295 K.
Collapse
|
73
|
Shestimerova TA, Oleneva OS, Mitiaev AS, Bykov MA, Davliatshin DI, Shevelkov AV. Synthesis, Structure, and Properties of Ag5Se(PO4) and Ag5Te(PO4) with Two-Dimensional Framework Trapping PO43-anions. Z Anorg Allg Chem 2009. [DOI: 10.1002/zaac.200801409] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
74
|
Zaikina JV, Kovnir KA, Haarmann F, Schnelle W, Burkhardt U, Borrmann H, Schwarz U, Grin Y, Shevelkov AV. The first silicon-based cationic clathrate III with high thermal stability: Si172-xPxTey (x=2y, y>20). Chemistry 2008; 14:5414-22. [PMID: 18504725 DOI: 10.1002/chem.200800453] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A new representative of a very rare clathrate III family, Si130P42Te21, has been synthesized from the elements. It crystallizes in the tetragonal space group P4(2)/mnm (no. 136) with the unit cell parameters a=19.2632(3) angstroms, c=10.0706(2) angstroms. Single crystal X-ray diffraction and solid state 31P NMR revealed a non-random distribution of phosphorus atoms over the framework positions. The crystal structure features a peculiar packing of large polyhedra Te@(Si/P)(n) never observed before for cationic clathrates. Despite the structural complexity, the composition of the novel clathrate Is in accordance with the Zintl rule, which was confirmed by a combination of optical metallography, scanning electron microscopy (SEM) and wavelength dispersive X-ray spectroscopy (WDXS), as well as by diamagnetic and semiconducting behavior of the synthesized phase. Clathrate Si130P42Te21 exhibits the highest reported thermal stability for this class of materials, it decomposes at 1510 K. This opens new perspectives for the creation of clathrate-based materials for high-temperature applications.
Collapse
|
75
|
Shevelkov AV. Chemical aspects of the design of thermoelectric materials. RUSSIAN CHEMICAL REVIEWS 2008. [DOI: 10.1070/rc2008v077n01abeh003746] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|