What is the Seebeck coefficient of bismuth telluride?
The Seebeck coefficient is −170 μV/K for the n-type material and 160 μV/K for the p-type material.
What is the formula for bismuth III telluride?
Bi2Te3Bismuth telluride / Formula
Why is bismuth telluride a good thermoelectric?
The large zT can be traced to the high band degeneracy, low effective mass, high carrier mobility, and relatively low lattice thermal conductivity, which all contribute to its remarkably high thermoelectric quality factor.
What is ZT in thermoelectrics?
Figure of merit is used to determine the efficiency of thermocouples and thermoelectric generators. In the corresponding formulas, the figure of merit appears under the name ZT. A temperature difference at the ends of an electrical conductor causes an electrical voltage in this conductor.
Is bismuth telluride toxic?
Acute Health Effects The following acute (short-term) health effects may occur immediately or shortly after exposure to Bismuth Telluride: * Contact can irritate the skin and eyes. * Breathing Bismuth Telluride can irritate the nose and throat.
What is Seebeck coefficient value?
The Seebeck coefficient of platinum itself is approximately −5 μV/K at room temperature, and so the values listed below should be compensated accordingly. For example, the Seebeck coefficients of Cu, Ag, Au are 1.5 μV/K, and of Al −1.5 μV/K.
What is ZT geometry?
The performance of a thermoelectric material is evaluated by the dimensionless figure of merit, ZT , which is defined as ZT = S 2σ T / k , where σ is the electrical conductivity, S is the Seebeck coefficient (i.e. thermopower), k is the thermal conductivity (often separated into the lattice thermal conductivity, k L.
What are the properties of bismuth?
Bismuth is a rather brittle metal with a somewhat pinkish, silvery metallic lustre. Bismuth is the most diamagnetic of all metals (i.e., it exhibits the greatest opposition to being magnetized). It is hard and coarsely crystalline. It undergoes a 3.3 percent expansion when it solidifies from the molten state.
What are the characteristics of bismuth?
Bismuth is a high-density, silvery, pink-tinged metal. Bismuth metal is brittle and so it is usually mixed with other metals to make it useful. Its alloys with tin or cadmium have low melting points and are used in fire detectors and extinguishers, electric fuses and solders.
Is the Seebeck coefficient constant?
2.3 Thermopower or Seebeck Coefficient The quantity, kB/e≈87μVK−1, is a constant, which represents the thermopower of a classical electron gas. Metals have thermopower values much less than 87 μV K−1 (on the order of 1–10 μV K−1) and decrease with decreasing temperature, i.e., EF≫kBT).
What Seebeck coefficient tells us?
The Seebeck coefficient (also known as thermopower, thermoelectric power, and thermoelectric sensitivity) of a material is a measure of the magnitude of an induced thermoelectric voltage in response to a temperature difference across that material, as induced by the Seebeck effect.