Work

Tunable p- and n-Type Tellurium-Free Mg 3 Bi 2 Thermoelectric Thin Films by Thermal Coevaporation

Year: 2023

Type: article

Abstract: Mg 3 Bi 2 has recently emerged as a promising environmentally friendly alternative to bismuth tellurides for near-room-temperature thermoelectrics. Here, we report on the fabrication of Mg 3 Bi 2 thin films under Mg-rich and Mg-poor conditions via vacuum thermal coevaporation. We demonstrate that under Mg-deficient conditions thin films show a p-type conduction behavior with a maximum power factor exceeding 300 μW m –1 K –2 and a thermoelectric figure of merit ZT of 0.11 at 200 °C. Increasing the amount of Mg enables the formation of Mg-rich Mg 3 Bi 2 thin films with n-type conduction. These films exhibit a maximum power factor and ZT at lower temperatures of around 130–140 °C. Moreover, the maximum ZT is increased to 0.19 due to the ultralow thermal conductivity of the n-type Mg 3 Bi 2 .

Source: ACS Applied Energy Materials

DOI: 10.1021/acsaem.3c01878

Authors: Joost W. C. Reinders, Cristina Roldán-Carmona, Henk J. Bolink, Francisco Palazon

Institutions: Universitat de València, Universidad Politécnica de Cartagena

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: green