Flexible thermoelectric device with excellent durability towards self-powered light intensity detection

Thermoelectric technology can generate thermoelectric electromotive force under the condition of temperature difference, which have unlimited prospects in the emerging fields of sensing, wearable electronic devices, self-powered arbitrary doors, electronic skin. These application scenarios also put forward higher requirements for thermoelectric devices, excellent flexibility and self-supporting characteristics. Herein, a novel flexible self-supported thermoelectric device based on carbon nanotubes (CNTs) was designed and constructed with simple laminated construction of electrical series and thermal parallel. CNTs/PEDOT:PSS and polyethylenimine (PEI)-doped CNTs/polyvinylidene fluoride (PVDF) flexible self-supported films were used as p- and n-type films respectively. The obtained flexible self-supported thermoelectric device can generate a voltage of 3.31 mV under temperature difference of 35 K. The excellent light absorption and photothermal conversion of CNTs, together with the thermoelectric characteristics of CNTs and PEDOT:PSS, enables its promising applications in self-powered light intensity detection. Furthermore, its excellent flexibility and self-supporting characteristics give it outstanding durability.