Time-Domain Thermoreflectance Study of the Thermal Transport Properties of All-Solid-State Ionic Thermoelectric Material

The emerging ionic thermoelectric (i-TE) materials are promising for waste heat recovery and temperature sensors due to their huge ionic Seebeck coefficients. However, rare work concentrates on studying the intrinsic thermal conductivity of i-TE materials and the interfacial thermal conductance with electrodes, which could significantly affect the performance of i-TE-based devices. In this work, the thermal transport properties of polymer-based i-TE films at various temperatures were investigated by the time-domain thermoreflectance method. Interestingly, the thermal conductivity of the polymer i-TE films was found to decrease with increasing temperature, showing a similar temperature-dependent trend with crystalline materials. Moreover, the interfacial thermal conductance between i-TE films and the metal electrode is similar to 50 MW center dot m(-2)center dot K-1, which is related to the rotation speed during the spin-coating process. The above finding is important to optimize the performance of the i-TE devices in practical applications.

Automated summary

The thermal transport properties of polymer-based i-TE films were investigated at different temperatures using the time-domain thermoreflectance method. It was found that the thermal conductivity of the polymer i-TE films decreases with increasing temperature, showing a similar temperature-dependent trend as crystalline materials. Moreover, the interfacial thermal conductance between the i-TE films and the metal electrode is around 50 MW·m(-2)·K-1, which is influenced by the rotation speed during the spin-coating process. These findings are crucial for optimizing the performance of i-TE devices in practical applications.