Humidity-resistant triboelectric nanogenerator and its applications in wind energy harvesting and self-powered cathodic protection

The triboelectric nanogenerator (TENG) is a novel energy harvesting strategy to convert various types of mechanical energy into electrical energy through the synergistic effect of triboelectrification and electrostatic induction. A hydrophobic polytetrafluoroethylene (PTFE) flexible film was introduced to establish a wind-driven TENG as the power supply for a self-powered cathodic protection (CP) system. The PTFE flexible film was used as the friction layer with polyvinyl alcohol (PVA) film to generate charges. The developed triboelectric charges were transferred to the cathodic protection system. The PTFE-based flexible TENG exhibits enhanced output performance with an optimized short current of 29.72 μA, an output voltage of 695.18 V, and an optimized power of 1.74 mW at 95% RH (Relative Humidity). Besides, through the external connection to the protected metal, the PTFE-based flexible TENG established the power supply of the self-powered anticorrosion system. In the electrochemical measurements, an apparent open-circuit potential drop (OCP) of 590 mV was achieved for the carbon steel connected with the wind-driven TENG, and the charge transfer resistance was also significantly reduced. Due to the high performance of the flexible TENG under high humidity, this smart self-powered system could effectively collect wind energy in the marine environment and prevent metal corrosion in marine facilities by converting wind power.