Soluble Sb₂Te₃ Molecular Precursor for Solution Processing of High-Performance Thermoelectric Thin Film

The recent interest in portable and wearable electronics lead flexible thin film thermoelectrics to be regarded as promising candidates for the power supply of self-powered systems. Herein, we report a cost-effective solution process to fabricate flexible Sb₂Te₃ thermoelectric thin films using molecular Sb₂Te₃ precursors, synthesized by the reduction of Sb₂Te₃ powder in ethylenediamine and ethanedithiol with superhydride. This synthetic route decreases the size of the Sb₂Te₃ precursor to the molecular level, thereby dramatically improving the uniformity and continuity of the thin film. Furthermore, thermally stable FePt nanoparticles are homogeneously embedded in the Sb₂Te₃ thin film by using the mixed ink solution. The fabricated Sb₂Te₃ thin films on flexible polyimide substrates exhibit a power factor of of ~8.5 μW cm^-1 K² at 423 K. Moreover, such thermoelectric performances of thin films are well preserved during 1000 bending cycles. The current study offers considerable potential for a cost-effective manufacturing for high-performance flexible thin film devices.