Topical review: characterization of chalcopyrite CuGa(In)Te₂ compounds for high thermoelectric performance

The chalcopyrite compound CuGa(In)Te-2 has garnered significant attention due to its safe elemental composition and high thermoelectric potential. Optimizing the carrier concentration and reducing the lattice thermal conductivity of CuGa(In)Te-2 can significantly enhance its thermoelectric performance. In this mini-review, we analyze the electronic and phonon structures of CuGa(In)Te-2, summarize and categorize the representative methods employed in recent years to improve its thermoelectric performance. Our analysis reveals that reducing thermal conductivity has a more significant impact on enhancing the ZT value of CuGa(In)Te-2 compared to increasing the power factor. In conclusion, we outline potential challenges and provide a brief outlook, offering valuable insights into the design of CuGa(In)Te-2 chalcopyrite compounds as high-performance thermoelectric materials.