The difference of temperature in a material can convert heat energy into electrical energy. To harvest the heat energy, the material should have

To efficiently harvest heat energy and convert it into electrical energy, the material should have high thermoelectric efficiency, which depends on the following key properties:

High Seebeck Coefficient (S) – The material should generate a large voltage difference when there is a temperature difference. A high Seebeck coefficient means greater thermoelectric voltage generation.

High Electrical Conductivity (σ) – The material should allow easy flow of charge carriers (electrons or holes) to minimize resistive losses.

Low Thermal Conductivity (κ) – The material should prevent heat from quickly dissipating through it. Low thermal conductivity helps maintain the temperature difference necessary for continuous energy conversion.

These properties are often measured by the thermoelectric figure of merit (Z_T), given by the formula:

$Z_T=\frac{S^2\sigma }{\kappa }T$

where:

$S$ is the Seebeck coefficient,

$\sigma$ is the electrical conductivity,

$\kappa$ is the thermal conductivity,

$T$ is the absolute temperature.