Thermoelectric generator based on anisotropic wood aerogel for low-grade heat energy harvesting

Thermoelectric generators(TEGs) have received increasing attention due to their potential to harvest low-grade heat energy(<100 °C) and provide power for the Internet of Things(Io T) and wearable electronic devices. Herein, a wood-based ordered framework is used to fabricate carbon nanotube/poly(3,4-ethylenedioxythiophene)(CNT/PEDOT) wood aerogel for TEG. The prepared CNT/PEDOT wood aerogel with an anisotropic structure exhibits a low thermal conductivity of 0.17 W m-1K-1and is advantageous to develop a sufficient temperature gradient. Meanwhile, CNT/PEDOT composites effectively decouple the relationship between the Seebeck coefficient and electrical conductivity by energy filtering effect to enhance thermoelectric(TE) output properties. The vertical TEG assembled by the CNT/PEDOT wood aerogels reveals an output power of 1.5 μW and a mass-specific power of 15.48 μW g-1at a temperature difference of 39.4 K. Moreover, the layered structure renders high compressibility and fatigue resistance.The anisotropic structure, high mechanical performance, and rapid thermoelectric response, enabling the TEG based on CNT/PEDOT wood aerogel offer opportunities for continuous power supply to low-power electronic devices.