Effect of Chemical Doping on the Thermoelectric Properties of FeGa3

TL;DR

This study investigates how chemical doping alters the thermoelectric properties of FeGa3, revealing increased carrier density and improved power factor, with potential implications for thermoelectric applications.

Contribution

It provides new insights into doping effects on FeGa3's thermoelectric performance, demonstrating enhanced power factor and stability of the Seebeck coefficient.

Findings

Chemical doping increases carrier density and induces metallic behavior.

The highest power factor achieved is 62 μW/m·K^2 at 390 K.

Doping maintains a large Seebeck coefficient despite increased conductivity.

Abstract

Thermoelectric properties of the chemically-doped intermetallic narrow-band semiconductor FeGa3 are reported. The parent compound shows semiconductor-like behavior with a small band gap (Eg = 0.2 eV), a carrier density of ~ 10(18) cm-3 and, a large n-type Seebeck coefficient (S ~ -400 \mu V/K) at room temperature. Hall effect measurements indicate that chemical doping significantly increases the carrier density, resulting in a metallic state, while the Seebeck coefficient still remains fairly large (~ -150 \mu V/K). The largest power factor (S2/{\rho} = 62 \mu W/m K2) and corresponding figure of merit (ZT = 0.013) at 390 K were observed for Fe0.99Co0.01(Ga0.997Ge0.003)3.