Global ETD Search
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Showing 1 to 20 of 20 for “"Bismuth telluride"”.
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Electronic Transport in Thermoelectric Bismuth Telluride
… of the electronic transport properties of bismuth telluride nanocomposite materials is presented. The primary transport measurements are electrical conductivity, Seebeck coefficient and Hall effect. An experimental apparatus for measuring Hall effect and electrical conductivity was …
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Application of Thermomechanical Characterization Techniques to Bismuth Telluride Based Thermoelectric Materials
The thermoelectric properties of bismuth telluride based thermoelectric (TE) materials are well-characterized, but comparatively little has been published on the thermomechanical properties. In this paper, dynamic mechanical analysis (DMA) and differential scanning calorimetry data for bismuth …
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LOW DIMENSIONAL CARBON BASED ORGANIC THERMOELECTRIC COMPOSITES: SYNTHESIS, CHARACTERIZATION, AND PERFORMANCE
… used room temperature thermoelectric material bismuth telluride nearly sixty years ago, the performance of thermoelectrics has seen little improvement. In recent years, slight improvements through the use of complex crystalline structures and nano arrays have renewed interest in …
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Electrodeposition of multilayered nanostructures for giant magnetoresistance and thermoelectric applications
… giant magneto resistance (GMR) applications and bismuth telluride nanotubes for thermoelectric applications are presented in this dissertation. The motivation for the multilayer electrodeposition is the investigation of giant magnetoresistance (GMR), a change in the material resistance in an …
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Characterizing the thermal efficiency of thermoelectric modules
… of temperature of a commercially available, bismuth telluride thermoelectric module. Thermoelectric modules are solid state semiconducting devices that act reversibly as both a heat pump and a power generator. The experimental setup encased the modules in an insulating container and thermal …
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Study of electrical and thermal transport in low-dimensional structures aiming for improving thermoelectric efficiency
… We calculate the thermal conductivity of layered bismuth telluride thin films by solving the Boltzmann transport equation in the relaxation-time approximation using full phonon dispersion. The full phonon frequency and gradient are obtained from the framework of the first-principle density …
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Artificial Anisotropy for Transverse Thermoelectric Heat Flux Sensing
… methods. The device tested is constructed out of bismuth telluride and titanium grade 5. Bismuth telluride is a standard thermoelectric material, while the titanium is used because of its high melting point and good electrical conductivity. The device is constructed by alternating rectangular …
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Modeling and Applications of Thermoelectric Generators
… are used to predict the harvested power. Bismuth-telluride is used as semiconductors materials of the TEG, which is the most commonly used material by industry. Experiments on three TEG modules were performed to validate the numerical model. A comparison with predicted levels of harvested …
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Low Temperature Growth and Characterization of ZnO Nanostructures
… proposed are Zinc Oxide (ZnO) nanowires and Bismuth Telluride (BiTe) nanowires, and the organic light absorber is a semiconductor porphyrin. To further develop and design this device, the two contact materials need to be characterized and further developed. This manuscript focuses on the …
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Controlling microstructure of nanocrystalline thermoelectrics through powder processing
Bismuth Telluride and its solid solutions are currently front running thermoelectric materials because of their high figure of merit. When processed via mechanical alloying to obtain nanocrystalline structures, their efficiency is increased dramatically, due to enhanced phonon scattering at grain …
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The Growth of Streptomycetes and Fungi Under Controlled Conditions on the Surface of Coated Materials
… the service life of a textile. A dual p.n.p. bismuth-telluride thermocouple hygrometer was devised capable of monitoring the relative humidities of the air mixing system. Gravity plate airspora isolations of Streptomyces spp. were performed in conjunction with fungal isolations, to assess the …
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Thermoelectrics and aerogels for solar energy conversion systems
… thermoelectric generators (TEGs) made of bismuth telluride and skutterudite alloys are modeled, optimized, built, and tested. These TEGs achieve a heat-to-electricity conversion efficiency of 10.7% at a hot side of 550° C, the highest TEG eciency reported in this temperature range. From …
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Analysis & characterization of a flow thermo-electrochemical cell for power generation & heat convection
… a typical sold-state TE device such as a bismuth telluride TE device, can generate up to 0.300 mV/K [31]. New reseach has emerged [25, 26, 14] focusing on liquid-based thermo-electrochemical (TEC) cells that take advantage of the temperature dependence of oxidation/reduction chemical …
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An air-breathing, portable thermoelectric power generator based on a microfabricated silicon combustor
… The system was integrated with commercial bismuth telluride thermoelectric modules to produce 5.8 W of electrical power with a chemical-to-electrical conversion efficiency of 2.5% (based on lower heating value). The energy and power densities of the demonstrated system were 321 Wh/kg and 17 …
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Transverse Thermoelectric Effects for Cooling and Heat Flux Sensing
… device was built out of bulk samples of bismuth and bismuth telluride, which are common thermoelectric materials. The device was constructed of alternating layers of the constituent materials to simulate the effects of an intrinsically anisotropic material. The device was tested for its …
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Template Directed Growth of Nb doped SrTiO₃ using Pulsed Laser Deposition
… Nb:STO) has a power factor comparable to that of bismuth telluride. Semiconductor nanostructures have demonstrated a decrease in thermal conductivity (κ) resulting in an increase in the thermoelectric figure of merit (ZT). Nanostructures of doped oxides like niobium doped strontium titanate, may …
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Thermodynamics of ionic liquid solvents in gas purification and exfoliation mechanisms: molecular dynamics simulation and Monte Carlo calculations
… In the first study, the exfoliation of bismuth telluride (Bi2Te3) as a well-know thermoelectric (TE) material was investigated. In the literature, it has been experimentally and computationally proven that producing a thinner layer of Bi2Te3 increases the “figure of merit” by reducing …
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Thermoelectric waste heat recovery in automobile exhaust systems: Topological studies and performance analysis
… employed in the higher temperature regions and Bismuth Telluride modules are used at lower temperature regions of the device. Power is optimized for rectangular configurations featuring longitudinal and transverse flow through the device and for hexagonal and cylindrical topologies as well. …
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Hybrid solar thermoelectric systems utilizing thermosyphons for bottoming cycles
… room temperature. The thermoelectric materials bismuth telluride, lead telluride, and silicon germanium were combined with thermosyphon material-working fluids of copper-water, stainless steel-mercury, and nickel-liquid potassium for this work. We solved the energy equation at the evaporator …
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SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED MATERIALS FOR THERMOELECTRIC ENERGY CONVERSION
In 2012, more than 58% of the energy produced in the US was rejected in the form of heat. The rapid development of thermoelectric materials in the past decade has raised new hopes for the possibility of directly converting some of this waste thermal energy back to electricity. However, the large …