Mechanism of low thermal conductivity for Fe76Si13B8Nb2Cu1 amorphous and nanocrystalline alloys at room temperature

The thermal conductivity of crystalline materials cannot be arbitrarily low as the intrinsic limit depends on the phonon dispersion. We used complementary strategies to suppress the contribution of the longitudinal and transverse phonons to heat transport in layered materials containing different types of intrinsic chemical interface. BiOCl and Bi2O2Se encapsulate these design principles for longitudinal and transverse modes respectively, and the bulk superlattice material Bi4O4SeCl2 combines these effects by ordering both interface types within its unit cell to reach an extremely low thermal conductivity of 0.1 W K−1 m−1 at room temperature along its stacking direction. This value comes within a factor of four of air. We demonstrated that chemical control of the spatial arrangement of distinct interfaces can synergically modify vibrational modes to minimize thermal conductivity.

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Where Should We Look For High Zt Materials: Suggestions From Theory.

MRS Proceedings ◽

10.1557/proc-626-z6.3 ◽

2000 ◽

Vol 626 ◽

Cited By ~ 1

Author(s):

M. Fornari ◽

D. J. Singh ◽

I. I. Mazin ◽

J. L. Feldman

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

First Principles ◽

Room Temperature ◽

First Principles Calculations ◽

High Electrical Conductivity ◽

Bulk Materials ◽

Low Thermal Conductivity ◽

Computational Exploration ◽

Single Material

ABSTRACTThe key challenges in discovering new high ZT thermoelectrics are understanding how the nearly contradictory requirements of high electrical conductivity, high thermopower and low thermal conductivity can be achieved in a single material and based on this identifying suitable compounds. First principles calculations provide a material specific microscopic window into the relevant properties and their origins. We illustrate the utility of the approach by presenting specific examples of compounds belonging to the class of skutterudites that are or are not good thermoelectrics along with the microscopic reasons. Based on our computational exploration we make a suggestion for achieving higher values of ZT at room temperature in bulk materials, namely n-type La(Ru,Rh)4Sb12 with high La-filling.

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Conductivity studies of Ni and Gd substituted BiCoO3

Modern Physics Letters B ◽

10.1142/s0217984914500341 ◽

2014 ◽

Vol 28 (05) ◽

pp. 1450034 ◽

Cited By ~ 1

Author(s):

T. Ramachandran ◽

N. E. Rajeevan ◽

P. P. Pradyumnan

Keyword(s):

Thermal Conductivity ◽

Room Temperature ◽

Structural Studies ◽

Reaction Route ◽

Low Thermal Conductivity ◽

Sem Micrograph ◽

New Material ◽

Cubic Structure ◽

Solid State Reaction Route ◽

Room Temperature Raman Spectrum

In this paper, we report the synthesis, thermal and electrical property studies of Ni 0.5 Gd 0.2 Bi 0.3 CoO 3, a new material for thermoelectric applications. The material was synthesized by solid state reaction route taking BiCoO 3 as basic matrix by substituting bismuth with nickel and gadolinium. Structural studies using room temperature XRD and room temperature Raman spectrum established cubic structure for Ni 0.5 Bi 0.5 CoO 3 and tetragonal structure for Ni 0.5 Gd 0.2 Bi 0.3 CoO 3. The SEM micrograph of the samples revealed crystallites of micrometer dimension with varying grain size. The sample showed interestingly low thermal conductivity and VRH mechanism was found to dominate in the electrical conduction at low temperature regime. The low thermal conductivity and moderate electrical conductivity is suggestive of strong candidature of the material for thermoelectric applications.

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Elephant ivory: A low thermal conductivity, high strength nanocomposite

Journal of Materials Research ◽

10.1557/jmr.2006.0029 ◽

2006 ◽

Vol 21 (1) ◽

pp. 287-292 ◽

Cited By ~ 29

Author(s):

Michael B. Jakubinek ◽

Champika J. Samarasekera ◽

Mary Anne White

Keyword(s):

Thermal Conductivity ◽

Room Temperature ◽

High Strength ◽

Mean Free Path ◽

Boundary Scattering ◽

Low Thermal Conductivity ◽

Recent Interest ◽

Elephant Ivory ◽

Nanocomposite Structures ◽

Structure Properties

There has been much recent interest in heat transport in nanostructures, and alsoin the structure, properties, and growth of biological materials. Here we present measurements of thermal properties of a nanostructured biomineral, ivory. The room-temperature thermal conductivity of ivory is anomalously low in comparison with its constituent components. Low-temperature (2–300 K) measurements ofthermal conductivity and heat capacity reveal a glass-like temperature dependenceof the thermal conductivity and phonon mean free path, consistent with increased phonon-boundary scattering associated with nanostructure. These results suggest that biomineral-like nanocomposite structures could be useful in the design of novel high-strength materials for low thermal conductivity applications.

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Unusually low thermal conductivity of atomically thin 2D tellurium

Nanoscale ◽

10.1039/c8nr01649f ◽

2018 ◽

Vol 10 (27) ◽

pp. 12997-13003 ◽

Cited By ~ 49

Author(s):

Zhibin Gao ◽

Fang Tao ◽

Jie Ren

Keyword(s):

Thermal Conductivity ◽

Room Temperature ◽

Low Thermal Conductivity

We firstly find that tellurene has a compellingly low room temperature κL of 2.16 and 4.08 W m−1 K−1 along the armchair and zigzag directions.

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Thermoelectric properties of the Al-TM-Si (TM = Mn, Re) 1/1-cubic approximant

MRS Proceedings ◽

10.1557/proc-805-ll3.3 ◽

2003 ◽

Vol 805 ◽

Cited By ~ 1

Author(s):

Tsunehiro Takeuchi ◽

Toshio Otagiri ◽

Hiroki Sakagami ◽

Uichiro Mizutani

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Low Thermal Conductivity ◽

Dimensionless Figure Of Merit

ABSTRACTThe electrical resistivity, thermoelectric power, and thermal conductivity were investigated for the Al71.6-xMn 17.4Six and Al71.6-xRe 17.4Six (7 ≤ x ≤ 12) 1/1-cubic approximants. A large thermoelectric power ranging from -40 to 90 μV/K and a low thermal conductivity less than 3 W/K·cm were observed at room temperatures. The electrical resistivity at room temperature for these approximants was kept below 4,000 μΩcm, that is much smaller than that in the corresponding quasicrystals. As a result of the large thermoelectric power, the low thermal conductivity, and the low electrical resistivity, large dimensionless figure of merit ZT = 0.10 (n-type) and 0.07 (p-type) were achieved for the Al71.6Re17.4Si11 and Al71.6Mn17.4Si11 at room temperature, respectively.

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Extremely Low Thermal Conductivity Substances as Novel Thermoelectric Materials

MRS Proceedings ◽

10.1557/proc-0886-f09-05 ◽

2005 ◽

Vol 886 ◽

Cited By ~ 3

Author(s):

Shinsuke Yamanaka ◽

Ken Kurosaki ◽

Atsuko Kosuga ◽

Keita Goto ◽

Hiroaki Muta

Keyword(s):

Thermal Conductivity ◽

Thermoelectric Properties ◽

Thermoelectric Materials ◽

Figure Of Merit ◽

Room Temperature ◽

State Of The Art ◽

Thermoelectric Figure ◽

Low Thermal Conductivity ◽

Thallium Compounds ◽

Thallium Tellurides

ABSTRACTWe have prepared polycrystalline bulk samples of various thallium compounds and measured their thermoelectric properties. The most remarkable point of the thermoelectric properties of the thallium compounds is the extremely low thermal conductivity. The state-of-the-art thermoelectric materials such as Bi2Te3 and TAGS materials indicate relatively low the thermal conductivity, around 1.5 W/m/K. However, the thermal conductivity of the thallium compounds is below 0.5 W/m/K; especially that of silver thallium tellurides is around 0.25 W/m/K at room temperature. This extremely low thermal conductivity leads a great advantage for an enhancement of the thermoelectric performance. In this paper, we report on the properties of some thallium compounds selected for study as novel thermoelectric materials. One of these compounds seems to have a thermoelectric figure of merit comparable to those of state-of-the-art materials.

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Thermoelectric Properties of Tl2Te-Sb2Te3 Pseudo-Binary System

MRS Proceedings ◽

10.1557/proc-0886-f08-03 ◽

2005 ◽

Vol 886 ◽

Author(s):

Ken Kurisaki ◽

Keita Goto ◽

Atsuko Kosuga ◽

Hiroaki Muta ◽

Shinsuke Yamanaka

Keyword(s):

Thermal Conductivity ◽

Binary System ◽

Thermoelectric Properties ◽

Room Temperature ◽

State Of The Art ◽

Electrical Performance ◽

Low Thermal Conductivity ◽

Maximum Value ◽

P Type ◽

Type Conduction

ABSTRACTPolycrystalline-sintered samples of thallium based substances, (Tl2Te)100−x(Sb2Te3)x (x= 0, 1, 5, 10), were prepared by melting Tl2Te and Sb2Te3 ingots followed by annealing in sealed quartz ampoules. The thermoelectric properties were measured from room temperature to around 600 K. The values of the Seebeck coefficient of all samples are positive, indicating a p-type conduction characteristic. The maximum value of the power factor is 6.53×10−4 Wm−1K−2 at 591 K obtained for x= 10 (Tl9SbTe6), which is about one order lower than those of state-of-the-art thermoelectric materials. All samples indicate an extremely low thermal conductivity, for example that of Tl2Te is approximately 0.35 Wm−1K−1 from room temperature to around 600 K. Although the electrical performance of the samples is not so good, the ZT value is relatively high due to the extremely low thermal conductivity. The maximum ZT value is 0.42 at 591 K obtained for Tl9SbTe6.

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Thermal conductivity and thermoelectric properties in 3D macroscopic pure carbon nanotube materials

Nanotechnology Reviews ◽

10.1515/ntrev-2021-0013 ◽

2021 ◽

Vol 10 (1) ◽

pp. 178-186

Author(s):

Xueming Yang ◽

Jixiang Cui ◽

Ke Xue ◽

Yao Fu ◽

Hanling Li ◽

...

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotube ◽

Thermoelectric Properties ◽

Room Temperature ◽

High Porosity ◽

Single Walled Carbon Nanotube ◽

Low Thermal Conductivity ◽

Multi Walled Carbon Nanotube ◽

Interconnected Structure ◽

Sintered Carbon

Abstract Sintered carbon nanotube (CNT) blocks and porous CNT sponges were prepared, and their thermoelectric properties were measured. The maximum dimensionless thermoelectric figure-of-merit, ZT, at room temperature of the sintered single-walled carbon nanotube (SWCNT) block is 9.34 × 10−5, which is twice higher than that of the sintered multi-walled carbon nanotube (MWCNT) block in this work and also higher than that of other sintered MWCNT blocks reported previously. In addition, the porous MWCNT sponge showed an ultra-low thermal conductivity of 0.021 W/(m K) and significantly enhanced ZT value of 5.72 × 10−4 at room temperature and 1 atm. This ZT value is higher than that of other 3D macroscopic pure CNT materials reported. The pronounced enhancement of the ZT in the porous MWCNT sponge is attributed to the ultra-low density, ultra-high porosity, and interconnected structure of the material, which lead to a fairly low thermal conductivity and better Seebeck coefficient. The finding of this work provides an understanding for exploring potential enhancement mechanisms and improving the thermoelectric properties of CNT-based thermoelectric composites.

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Effects of the Addition of Rhenium on the Thermoelectric Properties of the AlPdMn Quasicrystalline System

MRS Proceedings ◽

10.1557/proc-626-z5.1 ◽

2000 ◽

Vol 626 ◽

Author(s):

A. L. Pope ◽

R. Gagnon ◽

R. Schneidmiller ◽

P. N. Alboni ◽

R. T. Littleton ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Transport Property ◽

Periodic Structure ◽

Thermoelectric Properties ◽

Electrical Transport ◽

Room Temperature ◽

Phonon Scattering ◽

X Ray ◽

Low Thermal Conductivity

ABSTRACTPartially due to their lack of periodic structure, quasicrystals have inherently low thermal conductivity on the order of 1 - 3 W/m-K. AlPdMn quasicrystals exhibit favorable room temperature values of electrical conductivity, 500–800 (Ω-cm)-1, and thermopower, 80 μV/K, with respect to thermoelectric applications. In an effort to further increase the thermopower and hopefully minimize the thermal conductivity via phonon scattering, quartenary Al71Pd21Mn8-XReX quasicrystals were grown. X-ray data confirms that the addition of a fourth element does not alter the quasiperiodicity of the sample. Al71Pd21Mn8-XReX quasicrystals of varying Re concentration were synthesized where x had values of 0, 0.08, 0.25, 0.4, 0.8, 2, 5, 6, and 8. Both thermal and electrical transport property measurements have been performed and are reported.

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