Enhancing electricity generation at graphene–fluid interface under disturbance flow conditions

The conversion of flowing liquid water to electricity through graphene has attracted interest in basic physics and applications such as power generation systems. Although various mechanisms have been proposed to explain this phenomenon, the general theory remains unclear. In particular, these mechanisms often do not consider the fluid conditions, including disturbance, irregular, and laminar conditions. In this study, the contribution of the flow condition that enhances the electricity output performance was investigated through experiments using several types of fluidic chips and numerical calculations. Results indicate that the electromotive force cannot be determined by the Reynolds number, indicating that local flow conditions should be taken into account. Moreover, the electromotive force is increased by the inlet conditions that generate moderate irregularity in the flow condition near the inlet and transition to laminar flow in the fluidic channel. Our findings support the extension of current theories and provide valuable insights into basic science and industrial applications, especially for energy generation.