Triboelectric nanogenerators with groove textures and carbon fillers for self-powered cathodic protection.

Contact-separation mode triboelectric nanogenerators (CS-TENG) have received widespread attention in self-powered cathodic corrosion protection, but their relatively low output limits the application. This paper introduced both groove textures and carbon-fillers into CS-TENG and investigated the influences and mechanism of textures and filler parameters on the output of CS-TENG. Through the external connection to the protected metal, the CS-TENG with optimal textures and fillers established the power supply of the self-powered cathodic protection. It is shown that for CS-TENG with groove textures, a texture size of 10 μm-10 μm exhibits the maximum lateral deformation, which generates the largest contact area and lateral deformation, and thus outputs the highest voltage. Among the three selected carbon-fillers (carbon fibers, hard carbon particles, graphene oxide), carbon fibers with 0.5 wt% mass fraction provide the highest charge storage capacity and thus the largest electrical output. Compared to the CS-TENG without textures and fillers, the open-circuit voltage of CS-TENG with optimal textures and fillers increased by 165.08%. Cathode anti-corrosion experiments and EIS (electrochemical impedance spectroscopy) tests indicate that CS-TENG with optimal textures and fillers significantly reduce the electron transfer rate on the metal surface, exhibiting excellent anti-corrosion performance.