Electrical Transport Properties of the Pentatelluride Materials Hfte5 and Zrte5

1997 ◽  
Vol 478 ◽  
Author(s):  
T. M. Tritt ◽  
M. L. Wilson ◽  
R. L. Littleton ◽  
C. Feger ◽  
J. Kolis ◽  
...  
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Electrical Transport ◽  
Entire Range ◽  
Room Temperature ◽  
Polycrystalline Material ◽  
Polycrystalline Materials ◽  
Electrical Transport Properties ◽  
Low Dimensional ◽  
P Type

AbstractWe have measured the resistivity and thermopower of single crystals as well as polycrystalline pressed powders of the low-dimensional pentatelluride materials: HfTe5 and ZrTe5. We have performed these measurements as a function of temperature between 5K and 320K. In the single crystals there is a peak in the resistivity for both materials at a peak temperature, Tp where Tp ≈ 80K for HfTe5 and Tp ≈ 145K for ZrTe5. Both materials exhibit a large p-type thermopower around room temperature which undergoes a change to n-type below the peak. This data is similar to behavior observed previously in these materials. We have also synthesized pressed powders of polycrystalline pentatelluride materials, HfTe5 and ZrTe5. We have measured the resistivity and thermopower of these polycrystalline materials as a function of temperature between 5K and 320K. For the polycrystalline material, the room temperature thermopower for each of these materials is relatively high, +95 μV/K and +65 μV/K for HfTe5 and ZrTe5 respectively. These values compare closely to thermopower values for single crystals of these materials. At 77 K, the thermopower is +55 μV/K for HfTe5 and +35 μV/K for ZrTe5. In fact, the thermopower for the polycrystals decreases monotonically with temperature to T ≈ 5K, thus exhibiting p-type behavior over the entire range of temperature. As expected, the resistivity for the polycrystals is higher than the single crystal material, with values of 430 mΩ-cm and 24 mΩ-cm for Hfre5 and ZrTe5 respectively, compared to single crystal values of 0.35 mΩ-cm (HfTe5) and 1.0 mΩ-cm (ZrTe5). We have found that the peak in the resistivity evident in both single crystal materials is absent in these polycrystalline materials. We will discuss these materials in relation to their potential as candidates for thermoelectric applications.

scholarly journals Single Crystals of Electrically Conductive 2D MOFs: Structural and Electrical Transport Properties

2019 ◽  
Author(s):  
Robert W. Day ◽  
D. Kwabena Diako ◽  
Mehdi Rezaee ◽  
Lucas R. Parent ◽  
Grigorii Skorupskii ◽  
...  
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Electrical Transport ◽  
Prolonged Exposure ◽  
Metal Organic Frameworks ◽  
Two Dimensions ◽  
Conductivity Measurements ◽  
Electrical Transport Properties ◽  
Electrically Conductive ◽  
Metal Organic

Crystalline, electrically conductive, and intrinsically porous materials are rare. Layered 2D metal-organic frameworks (MOFs) break this trend. They are porous crystals that exhibit high electrical conductivity and are novel platforms for studying fundamentals of electricity and magnetism in two dimensions.1-8 Despite demonstrated applications,9-13 electrical transport in these remains poorly understood because of a lack of single crystal studies. Here, studies of single crystals of two 2D MOFs, Ni3(HITP)2 and Cu3(HHTP)2, uncover critical insights into their structure and transport. Conductivity measurements down to 0.3 K suggest metallicity for mesoscopic single crystals of Ni3(HITP)2, which contrasts with apparent activated conductivity for polycrystalline films. Microscopy studies further reveal that these MOFs are not isostructural as previously reported.14 Notably, single rods exhibit conductivities up to 150 S/cm, which persist even after prolonged exposure to the ambient. These single crystal studies confirm that 2D MOFs hold promise as molecularly tunable platforms for fundamental science and applications where porosity and conductivity are critical.<br>

Die elektrischen Transporteigenschaften von p- und n-Cd1-ϰ Znϰ Sb für 0≦ ϰ≦ 0,5 / The Electrical Transport Properties of p- and n-Cd1-ϰZnϰSb for 0≦ϰ≦0,5

1974 ◽  
Vol 29 (12) ◽  
pp. 1874-1889
Author(s):  
W. Lehnefinke
Keyword(s):  
Electrical Transport ◽  
Room Temperature ◽  
Anomalous Behavior ◽  
Special Treatment ◽  
Electrical Transport Properties ◽  
Temperature Range ◽  
Sign Change ◽  
Semiconducting Compounds ◽  
P Type ◽  
Type Conduction

The temperature dependence of electrical resistance, Hall coefficient, and thermoelectric power has been investigated in the temperature range from 10 K to room temperature. Undoped mixed crystals of the semiconducting compounds CdSb and ZnSb show p-type conduction in the whole temperature range. To get the n-type, samples of the composition Cd1-ϰZnϰSb with 0≦ϰ≦0,5 were doped with Se and Te. All Te-doped specimens show n-type conduction. In Se-doped samples n-conduction is achieved only for ϰ = 0 and ϰ = 0.1. Some of the doped samples change to p-type conduction at lower temperatures between 130 K and 210 k. In the region of the lowest measured temperatures a second sign change occurs to negative values again. A special treatment of the samples shows that this anomalous behavior is strongly affected by surface effects. By using a simple model for the structure of the samples these effects were explained.

scholarly journals Single Crystals of Electrically Conductive 2D MOFs: Structural and Electrical Transport Properties

2019 ◽  
Author(s):  
Robert W. Day ◽  
D. Kwabena Diako ◽  
Mehdi Rezaee ◽  
Lucas R. Parent ◽  
Grigorii Skorupskii ◽  
...  
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Electrical Transport ◽  
Prolonged Exposure ◽  
Metal Organic Frameworks ◽  
Two Dimensions ◽  
Conductivity Measurements ◽  
Electrical Transport Properties ◽  
Electrically Conductive ◽  
Metal Organic

Crystalline, electrically conductive, and intrinsically porous materials are rare. Layered 2D metal-organic frameworks (MOFs) break this trend. They are porous crystals that exhibit high electrical conductivity and are novel platforms for studying fundamentals of electricity and magnetism in two dimensions.1-8 Despite demonstrated applications,9-13 electrical transport in these remains poorly understood because of a lack of single crystal studies. Here, studies of single crystals of two 2D MOFs, Ni3(HITP)2 and Cu3(HHTP)2, uncover critical insights into their structure and transport. Conductivity measurements down to 0.3 K suggest metallicity for mesoscopic single crystals of Ni3(HITP)2, which contrasts with apparent activated conductivity for polycrystalline films. Microscopy studies further reveal that these MOFs are not isostructural as previously reported.14 Notably, single rods exhibit conductivities up to 150 S/cm, which persist even after prolonged exposure to the ambient. These single crystal studies confirm that 2D MOFs hold promise as molecularly tunable platforms for fundamental science and applications where porosity and conductivity are critical.<br>

Electrical transport properties of FeSe single crystal under high magnetic field

2021 ◽  
Vol 64 (8) ◽  
Author(s):  
HongHui Wang ◽  
ZhaoHui Cheng ◽  
MengZhu Shi ◽  
DongHui Ma ◽  
WeiZhuang Zhuo ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Single Crystal ◽  
Transport Properties ◽  
High Magnetic Field ◽  
Electrical Transport ◽  
Electrical Transport Properties

The Characteristic of the La3Ga5SiO14 Single Crystal Grown by Vertical Bridgman Method in Ar Atmosphere

2006 ◽  
Vol 510-511 ◽  
pp. 842-845 ◽  
Author(s):  
Noriko Bamba ◽  
Kentaro Kato ◽  
Toshinori Taishi ◽  
Takayuki Hayashi ◽  
Keigo Hoshikawa ◽  
...  
Keyword(s):  
Melting Point ◽  
Single Crystal ◽  
Single Crystals ◽  
Room Temperature ◽  
Color Change ◽  
Piezoelectric Materials ◽  
Lead Free ◽  
Piezoelectric Constant ◽  
Interstitial Oxygen ◽  
Vertical Bridgman

Langasite (La3Ga5SiO14: denoted by LGS) single crystal is one of the lead free piezoelectric materials with high piezoelectricity that is maintained up to its melting point (1470°C). Although LGS single crystals have usually been grown by Czochralski (CZ) method in oxygen contained atmosphere to prevent evaporation of Ga, they were grown by the vertical Bridgman (VB) method in Ar atmosphere without oxygen, and their properties were evaluated in this work. Transparent and colorless LGS single crystals were successfully obtained without Ga evaporation by the VB method in Ar atmosphere, and their resistivity at room temperature was much higher than that grown by conventional CZ method. Piezoelectric constant d11 of the crystal grown by the VB method was 6 x 10-12 C/N, which was close to that of the crystal grown by CZ method. The colorless transparent LGS single crystal turned to orange and its resistivity decreased by annealing in air. Since an orange-colored transparent LGS single crystal has been grown by conventional CZ method, this indicates that color change and the resistivity decrease of LGS crystal is caused by extra interstitial oxygen atoms in the crystal.

Electrical transport properties in nitrogen-doped p-type ZnO thin film

2006 ◽  
Vol 21 (12) ◽  
pp. 1522-1526 ◽  
Author(s):  
Z Y Xiao ◽  
Y C Liu ◽  
B H Li ◽  
J Y Zhang ◽  
D X Zhao ◽  
...  
Keyword(s):  
Thin Film ◽  
Transport Properties ◽  
Electrical Transport ◽  
Zno Thin Film ◽  
Electrical Transport Properties ◽  
Nitrogen Doped ◽  
P Type

Temperature Variation of Principal Moments of Some Polyatomic Crystals

1973 ◽  
Vol 28 (1-2) ◽  
pp. 23-25 ◽  
Author(s):  
O. P. Singhal
Keyword(s):  
Solid State ◽  
Temperature Coefficient ◽  
Single Crystals ◽  
Air Temperature ◽  
Entire Range ◽  
Room Temperature ◽  
Small Variation ◽  
Potassium Chromate ◽  
Absorption Frequency ◽  
Ammonium Dichromate

Principal moments of some of the polyatomic single crystals such as ammonium dichromate, ammonium chromate, potassium chromate and potassium permanganate have been determined from room temperature down to liquid air temperature. These have been found to decrease with the decrease of temperature. This variation is smaller in magnitude. It has been observed that the temperature coefficient of the principal moments has almost the same value over the entire range of temperature. This small variation of paramagnetism has been attributed to the variation of absorption frequency in solid state.

Sign in / Sign up

Export Citation Format

Share Document