Lightning‐Inspired Fluidic Nanogenerators With Intrinsic DC Output and High‐Efficiency Direct Charge Separation

Efficient energy harvesting from liquid flows is hampered by the alternating current (AC) output and rectification losses inherent in conventional electrostatic induction‐based triboelectric nanogenerators (TENGs). Herein, we report a lightning‐inspired TENG (LI‐TENG) that achieves intrinsic direct current (DC) output and high‐efficiency direct charge separation by mimicking atmospheric lightning dynamics within a modular two‐phase flow channel. By spatially modulating surface potentials using PTFE and PU, we orchestrate the orthogonal interaction between electrostatic forces and hydrodynamic shear stress, analogous to the gravity‐driven charge separation in cumulonimbus clouds. This biomimetic design enables direct charge transfer from water slugs to the electrodes, eliminating the need for external rectifiers and achieving a record‐high energy conversion efficiency of 5.88%—more than double that of electrostatic counterparts. Furthermore, the low‐force stereolithography (LFS) 3D‐printed modular architecture offers exceptional scalability. By establishing a high‐performance, rectification‐free power source, this work provides a validated technological platform for the realization of self‐powered, intelligent flow monitoring systems (“smart pipe”) in industrial IoT applications.