Ultralight PEDOT:PSS/graphene oxide composite aerogel sponges for electric power harvesting from thermal fluctuations and moist environment

Utilizing ubiquitous thermal evaporation for electrical energy harvesting is considered as an effective way to develop future green energy. In this work, we develop a lyophilized-prepared sponge based moist-electric generator with a supramolecular assembly of poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) and graphene oxide (PPGO), which could efficiently harvest electric power from thermal evaporation under extreme thermal fluctuations. More importantly, the open circuit voltage of self-power PPGO generator can reach up to 2.13 V in moist air (RH 73%) under a temperature difference of 110 K without any mechanical energy input, and 0.49 V cm−2 for an apparent area of ~1.25 cm2 under natural evaporation. In addition, the in situ Raman spectra indicate that the spontaneous symmetry breaking induced by assembly of PEDOT:PSS networks is responsible for the enhanced moist-electric power harvesting performance, which provides a convenient paradigm for converting waste heat and humid environmental energy into electricity.