Kihoi, S.K.Shenoy, U.S.Kahiu, J.N.Kim, H.Bhat, D.K.Lee, H.S.2026-02-042023Sustainable Energy and Fuels, 2023, 7, 8, pp. 1916-1929https://doi.org/10.1039/d3se00068khttps://idr.nitk.ac.in/handle/123456789/22017In the era of sustainable and environmentally friendly energy requirements, alternative sources of energy continue to be fervently sought after. Heat recovery into useful electrical energy from waste heat offers a readily available source of energy with humongous potential. Herein, a non-toxic thermoelectric material, SnTe, is explored. Promising thermoelectric performance is also communicated. Introducing Ge as a single dopant is shown for the first time in SnTe-based materials to introduce amorphous Ge (a-Ge) precipitates into the matrix. These act as an auxiliary contributor to the observed ultra-low lattice thermal conductivity of ∼0.33 W m−1 K−1 at 823 K, which is below the reported amorphous limit of SnTe. Bi, which is a known resonant dopant, was further co-doped to fine-tune the electrical properties where a high power factor of ∼25.7 μW cm−1 K−2 is reported. To push the limit of synergy, Sb was added raising the maximum figure of merit ZT to a value of ∼1.1 at 873 K. With co-doping, dual resonance levels are shown which distorts the density of states (DOS) contributing to an increased band effective mass. In conjunction with the introduction of an amorphous phase, co-doping is ascertained as a practical means for the synthesis of high-performance thermoelectric materials for effective waste-heat recovery applications. © 2023 The Royal Society of ChemistryCrystal latticesIV-VI semiconductorsThermal conductivityThermoelectric equipmentThermoelectricityTin compoundsWaste heat utilizationAlternative sources of energyCo-dopingElectrical energyEnergy from wastesEnergy requirementsLattice thermal conductivityNon-toxicSources of energyThermo-Electric materialsThermoelectric materialWaste heatamorphous mediumelectrical propertyinorganic compoundthermal conductivity