Harnessing the synergy of ultra-ductile cementitious composites and triboelectric yarns for enhanced energy harvesting

Cementitious composites are indispensable in infrastructure but are typically brittle and functionally inert. Engineered cementitious composites (ECC), known for their ultra-high ductility and strain-hardening behavior, provide a unique opportunity to synergize with triboelectric energy harvesting. Here, we report a multifunctional composite that integrates helically wrapped triboelectric yarns into ECC, where the material's intrinsic toughness and multi-cracking mechanisms stabilize and amplify triboelectric output. This synergy transforms ECC's deformation from a mechanical challenge into an electromechanical advantage, simultaneously enhancing damage tolerance and energy harvesting efficiency. The resulting ECC–yarn composite withstands repeated high-energy impacts without cracking, while delivering superior electrical performance (∼33 V, 19 nA, 5.8 nC under 50 N), significantly outperforming mortar-based counterparts. It maintains > 95 % output over 2000 cycles and enables diverse demonstrations, including powering LEDs, capacitor charging, real-time seismic detection, and AI-assisted gait recognition. This work illustrates how harnessing ECC's long-recognized toughness can unlock new functionalities in triboelectric nanogenerators, providing a synergistic pathway toward resilient, self-powered, and intelligent infrastructure.