scholarly journals Computationally Modelling the Use of Nanotechnology to Enhance the Performance of Thermoelectric Materials

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5096
Author(s):  
Peter Spriggs ◽  
Qing Wang
Keyword(s):  
High Temperature ◽  
Thermoelectric Materials ◽  
Phonon Scattering ◽  
Waste Heat ◽  
Global Climate ◽  
Computational Simulation ◽  
Electrical Energy ◽  
Maximum Efficiency ◽  
Temperature Range ◽  
Band Engineering

The increased focus on global climate change has meant that the thermoelectric market has received considerably more attention. There are many processes producing large amounts of waste heat that can be utilised to generate electrical energy. Thermoelectric devices have long suffered with low efficiencies, but this can be addressed in principle by improving the performance of the thermoelectric materials these devices are manufactured with. This paper investigates the thermoelectric performance of market standard thermoelectric materials before analysing how this performance can be improved through the adoption of various nanotechnology techniques. This analysis is carried out through the computational simulation of the materials over low-, mid- and high-temperature ranges. In the low-temperature range, through the use of nanopores and full frequency phonon scattering, Mg0.97Zn0.03Ag0.9Sb0.95 performed best with a ZT value of 1.45 at 433 K. Across the mid-temperature range a potentially industry leading ZT value of 2.08 was reached by AgSbTe1.85Se0.15. This was carried out by simulating the effect of band engineering and the introduction of dense stacking faults due to the addition of Se into AgSbTe2. AgSbTe1.85Se0.15 cannot be implemented in devices operating above 673 K because it degrades too quickly. Therefore, for the top 200 K of the mid-temperature range a PbBi0.002Te–15% Ag2Te nanocomposite performed best with a maximum ZT of 2.04 at 753 K and maximum efficiency of 23.27 at 813 K. In the high-temperature range, through the doping of hafnium (Hf) the nanostructured FeNb0.88Hf0.12Sb recorded the highest ZT value of 1.49 at 1273 K. This was closely followed by Fe1.05Nb0.75Ti0.25Sb, which recorded a ZT value of 1.31 at 1133 K. This makes Fe1.05Nb0.75Ti0.25Sb an attractive substitute for FeNb0.88Hf0.12Sb due to the much lower cost and far greater abundance of titanium (Ti) compared with hafnium.

Multimaterial Topology Optimization of Thermoelectric Generators

2019 ◽  
Author(s):  
Xiaoqiang Xu ◽  
Yongjia Wu ◽  
Lei Zuo ◽  
Shikui Chen
Keyword(s):  
Topology Optimization ◽  
Conversion Efficiency ◽  
Thermoelectric Materials ◽  
Power Plants ◽  
High Efficiency ◽  
Waste Heat ◽  
Computational Simulation ◽  
Oil Refining ◽  
Temperature Range ◽  
Multiple Materials

Abstract Over 50% of the energy from power plants, vehicles, oil refining, and steel or glass making process is released to the atmosphere as waste heat. As an attempt to deal with the growing energy crisis, the solid-state thermoelectric generator (TEG), which converts the waste heat into electricity using Seebeck phenomenon, has gained increasing popularity. Since the figures of merit of the thermoelectric materials are temperature dependent, it is not feasible to achieve high efficiency of the thermoelectric conversion using only one single thermoelectric material in a wide temperature range. To address this challenge, this paper proposes a method based on topology optimization to optimize the layouts of functional graded TEGs consisting of multiple materials. The objective of the optimization problem is to maximize the output power and conversion efficiency as well. The proposed method is implemented using the Solid Isotropic Material with Penalization (SIMP) method. The proposed method can make the most of the potential of different thermoelectric materials by distributing each material into its optimal working temperature interval. Instead of dummy materials, both the P and N-type electric conductors are optimally distributed with two different practical thermoelectric materials, namely Bi2Te3 & PbTe for P-type, and Bi2Te3 & CoSb3 for N-type respectively, with the yielding conversion efficiency around 12.5% in the temperature range Tc = 25°C and Th = 400°C. In the 2.5D computational simulation, however, the conversion efficiency shows a significant drop. This could be attributed to the mismatch of the external load and internal TEG resistance as well as the grey region from the topology optimization results as discussed in this paper.

Effect of Electron-Phonon Coupling on Transport Properties of Monolayers of ZrS2, BiI3 and PbI2: A thermoelectric Perspective

2021 ◽  
Author(s):  
Gautam Sharma ◽  
Vineet Kumar Pandey ◽  
Shouvik Datta ◽  
Prasenjit Ghosh
Keyword(s):  
Relaxation Time ◽  
Band Structure ◽  
Transport Properties ◽  
Thermoelectric Properties ◽  
Thermoelectric Materials ◽  
Waste Heat ◽  
Transport Coefficients ◽  
Electrical Energy ◽  
Phonon Coupling ◽  
Electron Phonon Coupling

Thermoelectric materials are used for conversion of waste heat to electrical energy. The transport coefficients that determine their thermoelectric properties depend on the band structure and the relaxation time of...

Topology Optimization of Multimaterial Thermoelectric Structures

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Xiaoqiang Xu ◽  
Yongjia Wu ◽  
Lei Zuo ◽  
Shikui Chen
Keyword(s):  
Topology Optimization ◽  
Thermoelectric Materials ◽  
Power Plants ◽  
High Efficiency ◽  
Waste Heat ◽  
Oil Refining ◽  
Numerical Verification ◽  
Temperature Range ◽  
Multiple Materials ◽  
P Type

Abstract A large amount of energy from power plants, vehicles, oil refining, and steel or glass making process is released to the atmosphere as waste heat. The thermoelectric generator (TEG) provides a way to reutilize this portion of energy by converting temperature differences into electricity using Seebeck phenomenon. Because the figures of merit zT of the thermoelectric materials are temperature-dependent, it is not feasible to achieve high efficiency of the thermoelectric conversion using only one single thermoelectric material in a wide temperature range. To address this challenge, the authors propose a method based on topology optimization to optimize the layouts of functional graded TEGs consisting of multiple materials. The multimaterial TEG is optimized using the solid isotropic material with penalization (SIMP) method. Instead of dummy materials, both the P-type and N-type electric conductors are optimally distributed with two different practical thermoelectric materials. Specifically, Bi2Te3 and Zn4Sb3 are selected for the P-type element while Bi2Te3 and CoSb3 are employed for the N-type element. Two optimization scenarios with relatively regular domains are first considered with one optimizing on both the P-type and N-type elements simultaneously, and the other one only on single P-type element. The maximum conversion efficiency could reach 9.61% and 12.34% respectively in the temperature range from 25 °C to 400 °C. CAD models are reconstructed based on the optimization results for numerical verification. A good agreement between the performance of the CAD model and optimization result is achieved, which demonstrates the effectiveness of the proposed method.

Highly efficient functional GexPb1−xTe based thermoelectric alloys

2014 ◽  
Vol 16 (37) ◽  
pp. 20120-20126 ◽  
Author(s):  
Yaniv Gelbstein ◽  
Joseph Davidow
Keyword(s):  
Energy Conversion ◽  
Fuel Consumption ◽  
Conversion Efficiency ◽  
Thermoelectric Materials ◽  
Waste Heat ◽  
Electrical Power ◽  
Electrical Energy ◽  
Energy Conversion Efficiency ◽  
Efficient Implementation ◽  
Thermoelectric Devices

Methods for enhancement of the direct thermal to electrical energy conversion efficiency, upon development of advanced thermoelectric materials, are constantly investigated mainly for an efficient implementation of thermoelectric devices in automotive vehicles, for utilizing the waste heat generated in such engines into useful electrical power and thereby reduction of the fuel consumption and CO2 emission levels.

Making Thermoelectric Materials SnxGa1−xNx Alloys by Magnetron Sputtering Technology

2015 ◽  
Vol 1120-1121 ◽  
pp. 490-492
Author(s):  
Xing Long Guo
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
Magnetron Sputtering ◽  
Thermoelectric Materials ◽  
Power Plants ◽  
Waste Heat ◽  
Heat Pumps ◽  
High Mechanical Strength ◽  
Power Generators ◽  
Device Operation

Thermoelectric materials are of interest for applications as heat pumps and power generators. Thermoelectric properties of SnxGa1−xN alloys have been investigated. It was found that as Sn concentration increases, the thermal conductivity decreases and power factor increases, which leads to an increase in the TE figure of ZT. The valuge of ZT was found to be 0.07 at 300 K for Sn0.38Ga0.64N alloy. The results indicate that SnGaN alloys could be potentially important TE materials for many applications, especially for prolonged TE device operation at high temperatures, such as for recovery of waste heat from automobile, aircrafts, and power plants due to their superior physical properties, including the ability of operating at high temperature/high power conditions, high mechanical strength and stability, and radiation hardness.

Ternary Copper-Based Diamond-Like Semiconductors for Thermoelectric Applications

2009 ◽  
Vol 1166 ◽  
Author(s):  
Donald T Morelli ◽  
Eric J. Skoug
Keyword(s):  
Thermoelectric Materials ◽  
Waste Heat Recovery ◽  
High Efficiency ◽  
Waste Heat ◽  
Low Cost ◽  
Electrical Energy ◽  
Clean Energy ◽  
Direct Conversion ◽  
Thermoelectric Device ◽  
Climate Control

AbstractThermoelectric materials can provide sources of clean energy and increase the efficiency of existing processes. Solar energy, waste heat recovery, and climate control are examples of applications that could benefit from the direct conversion between thermal and electrical energy provided by a thermoelectric device. The widespread use of thermoelectric devices has been prevented by their lack of efficiency, and thus the search for high-efficiency thermoelectric materials is ongoing. Here we describe our initial efforts studying copper-containing ternary compounds for use as high-efficiency thermoelectric materials that could provide low-cost alternatives to their silver-containing counterparts. The compounds of interest are semiconductors that crystallize in structures that are variants of binary zincblende structure compounds. Two examples are the compounds Cu2SnSe3 and Cu3SbSe4, for which we present here preliminary thermoelectric characterization data.

Penta-PdX2 (X = S, Se, Te) monolayers: promising anisotropic thermoelectric materials

2019 ◽  
Vol 7 (18) ◽  
pp. 11134-11142 ◽  
Author(s):  
Yang-Shun Lan ◽  
Xiang-Rong Chen ◽  
Cui-E Hu ◽  
Yan Cheng ◽  
Qi-Feng Chen
Keyword(s):  
Carbon Dioxide ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Thermoelectric Materials ◽  
Waste Heat ◽  
Electrical Energy ◽  
Gas Emissions

Thermoelectric materials can be used to convert waste heat into electrical energy, which is considered to be a cleaner form of energy that reduces carbon dioxide and greenhouse gas emissions.

Numerical Studies on the Performance of a Bubble Pump

2013 ◽  
Vol 330 ◽  
pp. 203-208 ◽  
Author(s):  
L. Bruno Augustin ◽  
Jigar Golecha ◽  
K.G. Sai Shreenaath ◽  
Vishnu Swami ◽  
M. Suresh
Keyword(s):  
Thermal Energy ◽  
Waste Heat ◽  
Electrical Energy ◽  
Operating Conditions ◽  
Maximum Efficiency ◽  
Working Fluid ◽  
Solar Thermal Energy ◽  
Thermally Driven ◽  
Absorption Refrigeration System ◽  
Bubble Pump

Increase in the consumption of electrical energy worldwide has laid the emphasis on replacing electrical energy with thermal energy wherever possible. In this paper, the bubble pump, which is ‘heart’ of diffusion- absorption refrigeration system, has been investigated numerically. A thermally driven bubble pump, which can be powered by waste heat or solar thermal energy, is used to lift the liquid. As a result of the absence of any mechanical moving part, the refrigerator is silent and very reliable in addition to aneconomicalandenvironmental friendlydevice. The concept of such a pump is already in existence but optimization studies are yet to be extensively investigated. This paper deals with the optimization of various parameters of the bubble pump usingwateras the working fluid. Parametric studies are carried out and a design optimization for maximum efficiency is performed for various operating conditions.Numerical simulation of the bubble pump is carried out using simple numerical equations which assume slug flow in the bubble pump. The diameter of the pipe and the position of the heating element are varied and the effect it has on time taken, pumping ratio and pumping ratio for one pumping cycle is studied.

scholarly journals Effects of Y, GdCu, and Al Addition on the Thermoelectric Behavior of CoCrFeNi High Entropy Alloys

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 781 ◽  
Author(s):  
Wanqing Dong ◽  
Zheng Zhou ◽  
Lijun Zhang ◽  
Mengdi Zhang ◽  
Peter Liaw ◽  
...  
Keyword(s):  
Thermoelectric Properties ◽  
Thermoelectric Materials ◽  
Alternative Energy ◽  
Phonon Scattering ◽  
Waste Heat ◽  
Second Phase ◽  
High Entropy Alloys ◽  
High Entropy ◽  
Alternative Energy Sources ◽  
The Future

Thermoelectric (TE) materials can interconvert waste heat into electricity, which will become alternative energy sources in the future. The high-entropy alloys (HEAs) as a new class of materials are well-known for some excellent properties, such as high friction toughness, excellent fatigue resistance, and corrosion resistance. Here, we present a series of HEAs to be potential candidates for the thermoelectric materials. The thermoelectric properties of YxCoCrFeNi, GdxCoCrFeNiCu, and annealed Al0.3CoCrFeNi were investigated. The effects of grain size and formation of the second phase on thermoelectric properties were revealed. In HEAs, we can reduce the thermal conductivity by controlling the phonon scattering due to the considerable complexity of the alloys. The Y, Gd-doped HEAs are competitive candidate thermoelectric materials for energy conversion in the future.

Sign in / Sign up

Export Citation Format

Share Document