Gas-driven triboelectric nanogenerator for mechanical energy harvesting and displacement monitoring

Gas as an energy carrier has been widely studied, ranging from small bubble motions to steam strike turbines. Despite the remarkable results, fewer studies have investigated the gas-driven liquid column movement commonly used in hydraulic systems, oil extraction, and other fields. Herein, we proposed a gas-driven triboelectric nanogenerator (GD-TENG) with liquid column motion for mechanical energy harvesting and displacement monitoring. When the gas drives a single liquid column to move inside a polytetrafluoroethylene (PTFE) tube, the solid-liquid interface of the GD-TENG can achieve efficient sliding friction and generate an open-circuit voltage of 15.9V. Meanwhile, the influence of some critical parameters such as liquid column length, PTFE tube wall thickness and liquid column motion speed on the output performance of GD-TENG are systematically investigated. Furthermore, the GD-TENG can successfully harvest mechanical energy to power microelectronic devices. A sensing system is designed based on the GD-TENG device for displacement monitoring of moving objects. This work provides a new research path in the field of mechanical energy harvesting and self-powered displacement monitoring.