Enhanced thermopower and low thermal conductivity in p-type polycrystalline ZrTe5

TL;DR

This study reports enhanced thermoelectric performance in polycrystalline p-type ZrTe5, showing high thermopower, low thermal conductivity, and improved figure of merit compared to similar materials, across a broad temperature range.

Contribution

It provides new insights into the thermoelectric properties of p-type ZrTe5, highlighting its potential for thermoelectric applications with improved efficiency.

Findings

High thermopower up to 458 μV/K at 340 K

Low thermal conductivity of 2 W/m-K at 300 K

Figure of merit zT increased by 63% over HfTe5

Abstract

Thermoelectric properties of polycrystalline p-type ZrTe5 are reported in temperature (T) range 2 - 340 K. Thermoelectric power (S) is positive and reaches up to 458 uV/K at 340 K on increasing T. The value of Fermi energy 16 meV, suggests low carrier density of ~ 9.5 X 10^18 cm-3. A sharp anomaly in S data is observed at 38 K, which seems intrinsic to p-type ZrTe5. The thermal conductivity value is low (2 W/m-K at T = 300 K) with major contribution from lattice part. Electrical resistivity data shows metal to semiconductor transition at T ~ 150 K and non-Arrhenius behavior in the semiconducting region. The figure of merit zT (0.026 at T = 300 K) is ~ 63% higher than HfTe5 (0.016), and better than the conventional SnTe, p-type PbTe and bipolar pristine ZrTe5 compounds.