Global ETD Search
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Showing 1 to 20 of 28 for “"Figure of Merit (ZT)"”.
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A Nanoengineering Approach to Oxide Thermoelectrics For Energy Harvesting Applications
The ability of uniquely functional thermoelectric materials to convert waste heat directly into electricity is critical considering the global energy economy. Profitable, energy-efficient thermoelectrics possess thermoelectric figures of merit ZT ≥ 1. We examined the effect of metal nanoparticle – …
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Study on Thermoelectricc Properties of Mg2(Sn,Si,Ge) for power generation applications
… at an alarming rate. During the production of electricity most of the energy is lost as heat. Thermoelectric devices can convert heat into electrical energy and vice versa. In the past decade there has been extensive research work to improve the efficiency of thermoelectric materials. …
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Numerical and Experimental Design of High Performance Heat Exchanger System for A Thermoelectric Power Generator for Implementation in Automobile Exhaust Gas Waste Heat Recovery
The effects of greenhouse gases have seen a significant rise in recent years due to the use of fossil fuels like gasoline and diesel. Conversion of the energy stored in these fossil fuels to mechanical work is an extremely inefficient process which results in a high amount of energy rejected in the …
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Template Directed Growth of Nb doped SrTiO₃ using Pulsed Laser Deposition
Oxide materials display a wide range of physical properties. Recently, doped complex oxides have drawn considerable attention for various applications including thermoelectrics. Doped complex oxide materials have high Seebeck coefficients (S) and electrical conductivities (o) comparable to other …
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Oxide based thermoelectric materials for large scale power generation
… gradient and electricity. The effectiveness of the material performance can be described by its figure of merit, ZT, which is defined as ZT = [alpha]²[sigma]T / [kappa] , where a is the Seebeck coefficient of the material, a is the electrical conductivity and [kappa] is the total thermal …
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Synthesis and physical characterization of thermoelectric single crystals
… on the synthesis and physical characterization of thermoelectric single crystals. 1In₄Se₃-[delta] crystals were grown by different methods including the use of a floating zone furnace and a three-zone furnace, as well as different initial compositions. The samples obtained each time, either …
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Modeling and characterization of thermoelectric properties of SiGe nanocomposites
… efficiency is related to the thermoelectric figure of merit ZT, which is proportional to the electrical conductivity, the square of the Seebeck coefficient, and the inverse of the thermal conductivity. Currently, the low ZT values of available materials restrict the large scale applications …
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Photoacoustic measurement of bandgaps of thermoelectric materials
Thermoelectric materials are a promising class of direct energy conversion materials, usually consisting of highly doped semiconductors. The key to maximizing their thermal to electrical energy conversion lies in optimizing three inter-related material properties, thermal conductivity, electrical …
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The Fabrication of Thermoelectric Materials Using Functionalised Silicon Nanoparticles
… (SiNPs) can be synthesised by a variety of methods. A one-pot synthesis based on the chemical reduction of inverse micelles has been used to produce SiNPs with ligands of varying alkyl chain length. These particles were characterised to determine how the chain length affects the surface …
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Electrical and thermal transport in 2- and 3-dimensional periodic holey silicon
Silicon, one of the most abundant elements on earth, is a promising candidate for thermoelectric applications in the form of different nanostructures. It has been conclusively demonstrated that boundary scattering in nanostructured silicon e ectively reduces thermal transport, resulting in an …
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Ab initio simulation and optimization of phonon drag effect for lower-temperature thermoelectric energy
… led to significant advances with a record-high zT above 2. However, the pursuit of higher TE performance at lower temperatures for cooling and refrigeration applications receives much less attention. Today's most widely-used thermoelectric materials below room temperature are still (Bi,Sb) …
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Understanding and designing carbon-based thermoelectric materials with atomic-scale simulations
… in solving the current global energy challenge of providing sustainable and clean energy. Nevertheless, thermoelectrics have long been too inefficient to be utilized due to the relatively low energy conversion efficiency of present thermoelectrics. One way to obtain improved efficiency is to …
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Thermoelectric properties of silicon-germanium alloys
… refrigeration. The energy conversion efficiency of thermoelectric devices is related to the thermoelectric figure of merit ZT, which is proportional to the electrical conductivity, the square of the Seebeck coefficient, and the inverse of the thermal conductivity. Currently, the low ZT values of …
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Thermoelectric Energy Conversion: First-principles Simulations, Energy Harvesting and Deep Cooling Systems
… efficiency is dominated by the materials’ figure of merit zT, which is linearly proportional to the electrical conductivity, the square of the Seebeck coefficient, and inversely proportional to the thermal conductivity. Researchers worldwide have made great progress finding materials with …
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Synthesis and thermoelectric properties of Mg2Si-Mg2Sn solid solutions for waste heat recovery
… vehicle waste-heat recovery owing to their high figure-of-merit (ZT), light weight, low cost, and non-toxicity. The optimized ZT of Mg2Si0.4Sn0.6 peaks at ∼ 750 K because its relatively narrow band gap results in the pronounced bipolar thermoelectric transport at higher temperatures. This bipolar …
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Thermoelectric characterization of one- and two- dimensional materials
… materials are useful for a wide range of applications like waste heat removal, solid state cooling, and power generation in space missions etc. A material's thermoelectric figure of merit (zT), which determines its performance in the applications listed above, depends on its Seebeck …
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Materials Physics for Thermoelectric and Related Energetic Applications
… and electrical power, which has a wide range of applications including power generation and refrigeration. The performance of thermoelectricity generation and the refrigeration is characterized by a dimensionless number called the Figure-of-Merit (ZT), defined as ZT = [sigma]-S 2T / [kappa], …
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Half-Heusler Thermoelectric Materials and Modules
… attention in recent years as it forms one of the largest sources of available energy. A rapid development of thermoelectric (TE) materials that can directly convert heat into electricity through the Seebeck effect, opens promising pathway for harvesting the thermal energy from the …
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Thermoelectric Energy Harvesting for Sensor Powering
… and sensor powering. The scientific innovations of this dissertation were based on the new advance on thermoelectric material, device optimization, fabrication methods, and system integration to increase energy conversion efficiency and reliability of the thermoelectric energy harvester. The …
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Thermoelectric and Charge Transport in Doped Semi-Crystalline Polymers
… cost, lightweight, mechanically robustness, ease of synthesis and tailoring material properties, environmental friendless, flexibility. For many of the mentioned applications, OSCs are doped to improve the conductivity. This is particularly important to improving the thermoelectric performance of …
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