Thermoelectric material achieves 13% waste heat conversion rate

Researchers at Queensland University of Technology (QUT) have developed a new thermoelectric material that achieves a record-high waste heat-to-electricity conversion efficiency of over 13%. By doping manganese into a silver-copper-telluride (AgCuTe) compound, the team enhanced the material’s electronic band structure, resulting in significantly improved thermoelectric performance. The prototype device demonstrated that for every 100 units of heat energy input, about 13 units were converted into electricity—an efficiency notably higher than typical thermoelectric materials, which usually convert only a few percent. The study, published in Energy & Environmental Science, reports a high dimensionless figure of merit (ZT) of approximately 1.88 at 773 K for the manganese-doped polycrystalline AgCuTe, one of the highest values recorded for this class of materials. This improvement is attributed to band convergence and valence band flattening, which enhance the power factor while maintaining low thermal conductivity through increased lattice defects.