Computer-aided design of high-efficiency GeTe-based thermoelectric devices

Driven by materials science development, the thermoelectric performance has been enhanced. However, only increasing the figure of merit to enhance the thermoelectric efficiency becomes more challenging. Here, we combine an enhanced figure of merit and geometry optimization of a device by computer-aided design to achieve a record-high thermoelectric efficiency of 16%. A figure of merit over 2.2 in p-type Ge1-x-yCrxSbyTe alloys is achieved resulting from the convergence of three valence edges induced by Cr doping to enhance the power factor and superlattice precipitates to lower the thermal conductivity. Using finite element analysis simulations, we optimize the geometry of a segmented thermoelectric device made of the as-developed Ge1-x-yCrxSbyTe and other reported materials, leading to a record high efficiency. Furthermore, our simulations on over 70 existing n-type thermoelectric materials can serve as a library to bridge the gap between materials science and device engineering to achieve high-efficiency thermoelectric devices.