Enhancing the thermoelectric performance of MgAgSb-based materials with heavy Zn-doped

The low intrinsic thermal conductivity, low cost, abundant element reserves, and superior mechanical qualities of MgAgSb-based near-room-temperature thermoelectric materials will eventually replace Bi₂Te₃-based materials. However, MgAgSb-based materials suffer from impurities that are caused by complicated phase transitions that reduce their thermoelectric properties. To create heavy Zn-doping MgAgSb-based materials, two-step differential ball milling and stoichiometric ratio regulation are used in this study. The second phases, pores, and some new phonon scattering centers are also provided by this technique, which leads to a low thermal conductivity of 0.8 W m⁻¹ K⁻¹. Meanwhile, significant Zn doping also optimizes the electrical properties. Finally, a doping level of 8% allows for a maximum zT value of 0.9 at 473 K. This strategy provides a straightforward solution without a lengthy annealing process. This technique encourages the use of MgAgSb-based products for commercial purposes.