Harnessing in-situ tribo-plasma emission for energy harvesting.

Electrostatic discharge (ESD) in triboelectrification is conventionally dismissed as an uncontrolled energy dissipation process. Here, we introduce an approach to harness tribo-plasma generated by spontaneous ESD between sliding dielectric materials. Leveraging the intrinsic triboelectric field, this mechanism drives in situ plasma generation and guides its directional emission, enabling direct electrical power output via simple wire electrodes. The resulting current can be configured as either quasi-square-wave alternating current or direct current, depending on the motion profile. Notably, the device exhibits exceptional constant-current performance, sustaining output with a minimal decay of 0.32 microampere at a load resistance of 500 megohms. The universality of this mechanism is validated across diverse materials, including polymers, fabrics, semiconductors, and metals. Beyond energy harvesting, the tribo-plasma generated by mechanical motion also shows proof-of-concept potential for surface modification, food preservation, and ion implantation. These findings establish a potential route for converting mechanical energy into electrical output and provide a foundation for power-source-free plasma technologies.