Grain Boundary Strengthening Achieves Extraordinary Module Efficiency in GeTe-Based Thermoelectric Materials
These videos have been matched automatically. Contact us if they are not relevant.
These videos have been matched automatically. Contact us if they are not relevant.
View abstract on PubMed
Summary
This summary is machine-generated.Researchers developed advanced Germanium Telluride (GeTe) thermoelectric materials with enhanced performance. This innovation boosts thermoelectric conversion efficiency and mechanical strength for better energy harvesting applications.
Area Of Science
- Materials Science
- Solid State Physics
- Nanotechnology
Background
- Planar defects like grain boundaries significantly affect phonon and carrier transport in Germanium Telluride (GeTe) thermoelectric materials.
- Achieving high thermoelectric figure of merit (zT) and mechanical robustness simultaneously in GeTe is challenging.
Purpose Of The Study
- To simultaneously enhance the thermoelectric figure of merit (zT) and mechanical strength of highly alloyed GeTe.
- To investigate the impact of Cd doping and Cu2Se-PbSe co-alloying on GeTe's thermoelectric and mechanical properties.
Main Methods
- Cd doping and Cu2Se-PbSe co-alloying of GeTe.
- Formation of dense nano-grain boundaries and point defects to scatter phonons.
- Optimization of carrier concentration and valence band convergence for improved electronic transport.
Main Results
- Achieved a peak zT of 2.1 at 700 K and an average zT of 1.4 (300-800 K) in (Ge0.98Cd0.02Te)0.88(Cu2Se)0.02(PbSe)0.1.
- Obtained high Vickers hardness of approximately 210 HV due to hierarchical structures.
- Fabricated a thermoelectric module with 0.86 W cm-2 output power density and 11% conversion efficiency at ΔT = 501 K.
Conclusions
- Simultaneous optimization of phonon scattering and electronic transport leads to superior thermoelectric performance in alloyed GeTe.
- The developed GeTe material exhibits excellent mechanical strength, crucial for practical thermoelectric device applications.
- The synergistic improvements in zT and mechanical properties enable high-efficiency thermoelectric energy conversion.
These videos have been matched automatically. Contact us if they are not relevant.
These videos have been matched automatically. Contact us if they are not relevant.
Related Concept Videos
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in...
When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...
Thermal strain is a concept that arises when we consider how temperature changes affect structures. Unlike the conventional assumption that structures remain constant under load, real-world scenarios often involve temperature fluctuations that can significantly impact these structures. Consider a homogeneous rod with a uniform cross-section resting freely on a flat horizontal surface. If the rod's temperature increases, the rod elongates. This elongation is proportional to the temperature...
Consider an external electric field propagating through a homogeneous medium. When the electric field crosses the surface boundary of the medium, it undergoes a discontinuity. The electric field can be resolved into normal and tangential components. The amount by which the field changes at any boundary is given by the difference between the field components above and below the surface boundary.
The surface integral of an electric field is given by Gauss's law in integral form and is related...
In convection, thermal energy is carried by the large-scale flow of matter. Ocean currents and large-scale atmospheric circulation, which result from the buoyancy of warm air and water, transfer hot air from the tropics toward the poles and cold air from the poles toward the tropics. The Earth’s rotation interacts with those flows, causing the observed eastward flow of air in the temperate zones. Convection dominates heat transfer by air, and the amount of available space for the airflow...
Understanding heat transfer mechanisms is essential for understanding how our bodies maintain balance in different environmental conditions. When the environment is thermoneutral, the body is in a state of balance, neither using nor releasing energy to maintain its core temperature. However, when the environment is not thermoneutral, the body employs four heat transfer mechanisms to maintain homeostasis: conduction, convection, evaporation, and radiation. These mechanisms facilitate heat...