Youbo Nan, Xiutong Wang, Xiaofan Zhai, Weijie Fan, Yanan Sun, Hui Zhou, Y. Huang
Harnessing the synergy of solar and mechanical energy presents a potential strategy for high‐efficiency photoelectrochemical cathodic protection. Herein, a Chitosan/NiFe 2 O 4 /TiO 2 (CS/NiFe 2 O 4 /TiO 2 ) ternary heterojunction with dual S‐scheme charge‐transfer channels is rationally designed, which strategically preserves high‐energy electrons and holes while quenching low‐activity carriers through interfacial band alignment. To enhance energy capture from mechanical sources, we developed Ecoflex composite dielectric properties to build a triboelectric nanogenerator (TENG). The integrated self‐powered cathodic protection system dynamically couples triboelectricity and photoelectrochemistry, where TENG‐generated electric fields accelerate carrier separation in the heterojunction, resulting in a cathodic polarization shift of −0.517 V vs SCE for 304 stainless steel (304ss) protection. This represents a 148% enhancement in cathodic polarization shift (ΔE = |−0.517 to (−0.209)| = 0.308 V) compared to solar‐only operation (−0.209 V vs SCE), demonstrating the superior protective efficacy enabled by the integrated energy harvesting strategy. This work establishes a sustainable paradigm for self‐powered anticorrosion technologies in the marine environment.