Abstract
The density-of-states effective mass (md*) is commonly obtained by fitting the equation, S = (8π2kB2/3eh2)md*T(π/3n)2/3(S, T, and n are the Seebeck coefficient, temperature, and the carrier concentration, respectively), to n-dependent S measurement. However, n is not a measurable parameter. It needs to be converted from the measured Hall carrier concentration (nH) using the Hall factor (rH= n/nH). The rHof material can be estimated by Single Parabolic Band (SPB) model if the band that contributed to transport is approximated to be parabolic and acoustic phonons dominantly scatter its carriers. However, the measurable nHis often used instead of n when utilizing the above equation due to the complex Fermi integrals involved in the SPB model calculation. Consequently, the md∗ estimated from the above equation while using nHwould be inaccurate. We propose the equation rH= 1.17 - [0.216 / {1 + exp((|S| - 101) / 67.1)}] as a simple and accurate method to obtain the rHfrom the measured S to facilitate the conversion from nHto n and eventually increase the accuracy of md∗ estimated from the above equation.
Original language | English |
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Pages (from-to) | 4036-4040 |
Number of pages | 5 |
Journal | ACS Applied Energy Materials |
Volume | 5 |
Issue number | 4 |
DOIs | |
State | Published - 25 Apr 2022 |
Keywords
- Hall carrier concentration
- Hall factor
- Seebeck coefficient
- density-of-states effective mass
- thermoelectric