Perovskite Materials: Potential Star in the Field of Thermoelectricity
In the face of the increasingly severe energy challenges, perovskite materials have received extensive attention in the fields of optoelectronics and thermoelectrics due to their easy synthesis and stability as energy conversion substances.Several theoretical and experimental studies have shown that the outstanding thermoelectric potential inherent in diverse organic and inorganic perovskite materials.It is noteworthy for its exceptional performance in terms of both electrical and thermal conductivity.To promote the application of perovskite materials in the field of thermoelectrics, the current research emphasizes on finding perovskite materials with thermoelectric potential and enhancing the thermoelectric performance of existing materials.First, this paper reviews the fundamental theories of perovskite and thermoelectric materials, describes the characterization parameters of material thermoelectric performance, and then elaborates on the research progress of perovskite materials with excellent thermoelectric potential, including inorganic chalcogenide and halide perovskite materials, organic composite perovskite materials, and oxide perovskite materials.Among them, inorganic chalcogenide and halide perovskite materials have been found to have extremely high thermoelectric figures of merit, comparable to or even better than well-known thermoelectric materials in terms of Seebeck coefficient, power factor, electron thermal conductivity, and lattice thermal conductivity.For example, various chalcogenide perovskite materials such as CaZrS3, CaZrSe3, and BaZrS3, as well as various halide perovskite materials such as Rb2SnI6, CsPbBr3, and CsSnI3, exhibit large Seebeck coefficient and ultra-low lattice thermal conductivity.Their thermoelectric figures of merit can reach around 1 or even exceed 4 for CaZrS3 at high temperatures, indicating that perovskite materials have the potential to become a new choice for thermoelectric applications.Simultaneously, at the same time, the anisotropic property has been observed clearly on the thermoelectric performances of chalcogenide perovskite along different lattice directions, providing a new direction for improving the thermoelectric performance of perovskite materials.In addition to the aforementioned inorganic perovskite materials, organic-inorganic hybrid perovskites are characterized by ultra-low thermal conductivity and outstanding Seebeck effect, having exceptional potential as thermoelectric material.At a temperature of 800 K, the ZT values of the inorganic halide CsSnCl3 and the organic-inorganic hybrid material CH3NH3SnCl3 are 0.62 and 0.67, respectively, being regarded as a potential candidate material for high-temperature thermoelectric systems.Furthermore, the ZT values of the double perovskite materials (NH4)2AgGaBr6 and (NH4)2AgAlBr6 reach up to 0.737 and 0.734, respectively, further highlighting their significant potential in terms of thermoelectric performance.Then, the paper provides a concise overview of the research advancements in organic-inorganic hybrid perovskite materials and oxide perovskite materials in the field of thermoelectric applications, including high Seebeck voltage thermoelectric module, infrared photo-thermoelectric imaging and photo-thermoelectric nanogenerator.Finally, the paper summarizes the key factors influencing the thermoelectric performance of materials.Utilizing band-engineering and doping control techniques, the electronic structure of materials can be effectively enhanced to optimize the electrical properties of the material.Additionally, precise control over the microstructure of materials enables adjustments to the phonon dispersion relation, thereby reducing lattice thermal conductivity.Ultimately, synergistically controlling both the electrical and thermal properties of materials contributes to enhancing thermoelectric performance.On the basis of current research, the potential applications of perovskite materials in thermoelectric systems are prospected.