High-Performance Flexible Thermoelectric Devices Based on All-Inorganic Hybrid Films for Harvesting Low-Grade Heat

The fabrication of a flexible thermoelectric (TE) device that contains flexible, all-inorganic hybrid thin films (p-type single-wall carbon nanotubes (SWCNTs)/Sb 2 Te 3 and n-type reduced graphene oxide (RGO)/Bi 2 Te 3 ) is reported. The optimized power factors of the p-type and n-type hybrid thin films at ambient temperature are about 55 and 108 µW m −1 K −2 , respectively. The high performance of these films that are fabricated through the combination of vacuum filtration and annealing can be attributed to their planar orientation and network structure. In addition, a TE device, with 10 couples of legs, shows an output power of 23.6 µW at a temperature gradient of 70 K. A prototype of an integrated photovoltaic-TE (PV-TE) device demonstrates the ability to harvest low-grade “waste” thermal energy from the human body and solar irradiation. The flexible TE and PV-TE device have great potential in wearable energy harvesting and management.