Natural Evaporation-Driven Ionovoltaic Electricity Generation

Evaporation-induced electricity generation, harnessing natural vaporization of water, is spotlighted as a promising energy conversion system with showing off remarkable characteristics such as continuous generation without artificial water motions. However, the vague origin and mechanism of this phenomenon are obstacles for practical application. Herein, the origin of the evaporation-induced electricity generation was verified in terms of the “ionovoltaic” effect, ionic motion-induced charge carrier flows, through a resistance-controllable metal oxide platform. The device, composed of solvothermal-grown zinc oxide, showed output signals of ∼0.4 V and ∼20 nA. This study improves an understanding of the evaporative ionovoltaic mechanism and secures applicability to various materials for future energy conversion devices.