Tailoring Ge-Sb-Te alloys for thermoelectric applications: A review on insights from doping studies

Abstract

Ge-Sb-Te (GST) alloys have garnered considerable interest due to their rapid crystallization rates, thermal stability, and reversible phase change. These characteristics make them promising candidates for various applications, including thermoelectric energy conversion. Doping GST alloys has been found to enhance their thermal stability and modify the temperature at which the amorphous-to-crystalline phase transition occurs. The doping process alters the excitation energy and transition temperature of the material allowing customization for specific applications. It gives useful insights to tailor the composition of GST alloys for improved thermoelectric performance. Understanding of these processes can aid in the development of high-performance GST alloy-based thermoelectric devices, enabling efficient energy conversion and utilization of waste heat. This review discusses the potential of GST as a thermoelectric material and examines the effect of doping on its characteristics. The article begins with thermoelectric fundamentals followed by a discussion on unique properties of GST. It provides a brief explanation of the techniques used to boost the ZT value. Additionally, it discusses various strategies to get around the interdependency of factors and increase ZT. Further experimental and theoretical studies are necessary to completely utilize the potential of GST alloys in thermoelectric applications.