Important Progress in Wearable Flexible Thermoelectric Devices New Inorganic Material Discovered
TapTechNews July 12th news, with the continuous development of flexible electronic devices, the design and development of wearable flexible thermoelectric devices have received much attention. In order to meet the performance requirements of flexible thermoelectric devices, a new inorganic material with both plasticity and high thermoelectric performance is needed.
The research team of Harbin Institute of Technology Shenzhen Campus has made important progress in the field of plastic thermoelectric materials and discovered that magnesium bismuthide (Mg₃Bi₂) single crystal has both excellent plastic deformation ability and outstanding thermoelectric performance at room temperature. The research results were published in Nature.
TapTechNews attached paper link: https://www.nature.com/articles/s41586-024-07621-8
The research team prepared centimeter-level high-quality magnesium bismuthide single crystal, which shows excellent plastic deformation ability at room temperature and can easily achieve various types of plastic deformation such as bending and twisting at room temperature.
The compressive strain in the in-plane direction of magnesium bismuthide single crystal exceeds 75%, and the tensile strain is up to 100%, which is one order of magnitude higher than that of traditional thermoelectric materials and even exceeds some metallic materials with similar crystal structures (such as titanium, magnesium, zirconium, cobalt and hafnium).
Most traditional high-performance thermoelectric materials are inorganic semiconductors, and the materials are prone to fracture under bending and tensile states. In contrast, organic semiconductors usually have good deformation ability, but the thermoelectric performance is generally lower than that of inorganic materials.
The optimized magnesium bismuthide single crystal also shows excellent thermoelectric performance at room temperature. The tellurium-doped magnesium bismuthide (Mg3Bi1.998Te0.002) single crystal has a thermoelectric power factor of about 55 μWcm-1 K-2 in the in-plane direction, and the room temperature thermoelectric figure of merit zT is about 0.65, with both excellent plasticity and thermoelectric performance.