Abstract: How to use water evaporation energy which is widely existing in nature is a challenging subject. In this paper, graphene oxide (GO) with abundant functional groups and excellent hydrophilicity was used as the power generation material, and reduced graphene oxide (RGO) prepared by hydrazine reduction was used as the electrode material. GO/RGO flexible generator was assembled by a simple dropping method on the polyethylene terephthalate (PET) substrate. The working area of GO film generator was fixed as 4.5 cm by 1.5 cm, and its power generation performance induced by water evaporation was studied. Driven by natural water evaporation at room temperature, it can output an open circuit voltage (V_oc) of 90 mV and a short circuit current (I_sc) of 0.6 μA as well as power density of 1.25 μW/cm³. The generator also exhibits excellent flexibility and high stability. Based on the classic flow potential theory, the mechanism of GO/RGO generator induced by water evaporation is proposed. This paper provides a new way for the use of water evaporation energy with simple steps, low cost and stable performance.

Key words: water evaporation energy, graphene oxide, self-driven generator, flexible generator