Flexible and thermostable thermoelectric devices based on large-area and porous all-graphene films

Thermoelectric (TE) generators, being able to convert temperature gradients into electricity, are an appealing eco-friendly energy harvesting technology. In order to broaden the applications of TE materials, many researchers have focused their efforts towards flexible TE materials to substitute the commercial rigid TE devices. Most of these works used polymers as flexible TE materials, but their lower efficiency and melting point in comparison to inorganic TE materials are limiting factors for many applications. Here, we report the fabrication of a flexible and thermostable TE generator based on porous all-graphene films. The output power of the generator is up to 0.43 μW for a temperature gradient of 75 K. In addition, it runs at 550 K higher temperature than current flexible TE devices, which allows its application at much higher temperatures than conventional flexible TE.