Strategies to advance thermoelectric performance of PbSe and PbS materials

Abstract Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa, making them promising for waste heat recovery and efficient cooling systems. Currently, extensively investigated thermoelectric materials such as Bi 2 Te 3 , PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature regions. However, the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth’s crust. Over the past few years, researchers have shown increasing interest in PbSe‐ and PbS‐based materials, primarily attributed to their abundant elemental supply and relatively low costs. The assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric performance. These strategies include optimizing carrier concentration (aliovalent doping, dynamic doping and defect state), enhancing density‐of‐state effective mass (band convergence, band flattening and energy filtering effect), optimizing carrier mobility (band sharpening and band alignment) and reducing lattice thermal conductivity (all‐scale hierarchical defect structures designing). This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.