Transferable and flexible thermoelectric thin films based on elemental tellurium with a large power factor

The development of high performance flexible thermoelectric materials is important for fabricating wearable thermoelectric generators that can directly convert waste body heat into electricity. In this work, flexible thermoelectric thin films based on elemental tellurium have been fabricated via electrodeposition followed by a transfer process using adhesive substrates, which show not only high flexibility but also a large power factor of 3.21 μW cm−1 K−2 at room temperature. The flexible thermoelectric thin films can be activated by the heat of fingertips, and a large output voltage of 15 mV can be generated thanks to the large room temperature Seebeck coefficient of the films. It is anticipated that this work may pave the way for fabricating low cost and high performance flexible thermoelectric thin films.