Self-charging protective layer for marine reinforced concrete based on arch-shaped triboelectric nanogenerator

In this work, a new strategy to improve the ability of protective layer against wave scouring damage in the splash zone is proposed by developing a protective layer based on triboelectric nanogenerator (TENG). TENGs endow the protective layer with the wave energy harvest ability during wave scouring the concrete structure. The harvesting process, facilitated by the elastic deformation of TENG, mitigates the impact of ocean waves on both protective layer and the concrete. Importantly, this process concurrently generates electrical energy, subsequently utilized to support a cathodic protection system, thereby providing an additional layer of defense for the rebar. A systematical investigation into the performance of the self-charging protective layer is conducted, revealing crucial insights and design guidelines for the implementation of this self-charging protective layer. The self-driven cathodic protection system proves highly effective in safeguarding the rebar, including a substantial drop in the open current potential (OCP) of rebar from - 584 mV (vs. SCE) to - 1121 mV (vs. SCE). Based on this protective layer, a protection system from concrete surface to rebar was constructed, inspiring a comprehensive way to prevent ion diffusion and inhibit rebar erosion for concrete protection.