A high performance eco-friendly MgAgSb-based thermoelectric power generation device near phase transition temperatures

The utilization of thermoelectric (TE) technology for eco-friendly energy harvesting presents a promising solution for off-grid power generation from waste heat. Despite the dominance of Bi2Te3 TE devices in the current market, their widespread application is hindered by the scarcity of Te and the fragile electrode contact interface. In this study, we introduce a novel thermoelectric interface material (TEiM), AgMgMn0.1, for the MgAgSb TE material, utilizing a multi-element alloying approach. This results in an advanced interface with a high bonding strength of 34.5 MPa and a low contact resistivity of 4.5 mu omega cm2, thereby overcoming the phase transition stress. In situ microstructure characterization and simulation demonstrate robust stability near phase transition temperatures and a low maximum von Mises stress, respectively. Additionally, we achieved a high performance MgAgSb-based device, with a maximum conversion efficiency of 9.1% at a temperature difference of 325 degrees C. These values surpass those of commercial Bi2Te3 products at low-grade temperature ranges. Eco-friendly MgAgSb-based Te-free TE devices offer a reliable solution for waste heat harvesting. The utilization of thermoelectric (TE) technology for eco-friendly energy harvesting presents a promising solution for off-grid power generation from waste heat.