Mechanical Energy‐Harvesting Piezo‐Biocatalytic Heterojunction for Sustainable Marine Antifouling

Marine biofouling represents a persistent threat to sustainable ocean industries, elevating operational costs and accelerating infrastructure degradation. While conventional biocide‐releasing coatings demonstrate antifouling efficacy, their environmental toxicity necessitates the development of eco‐friendly alternatives. Herein, we present a mechanical energy‐harvesting piezo‐biocatalytic system for sustainable marine antifouling, leveraging a CeO 2 ‐BaTiO 3 (Ce‐BTO) heterojunction with a synergistic triple‐catalytic mechanism. The integration of piezoelectric BaTiO 3 and CeO 2 nanozyme not only enhances charge separation and suppresses recombination to boost piezocatalytic reactive oxygen species (ROS) generation, but also exploits an electron injection effect to augment haloperoxidase‐like activity, enabling in situ production of biocidal hypobromous acid (HOBr) in seawater. Furthermore, Ce‐BTO exhibits DNA hydrolase‐like activity that specifically degrades extracellular DNA (eDNA)—a key structural component of extracellular polymeric substances—thereby disrupting biofilm integrity. This concerted action of ROS/HOBr‐mediated biocidal effects and eDNA hydrolysis confers Ce‐BTO with potent, broad‐spectrum anti‐microbial and anti‐algal performance, while remaining non‐toxic to non‐target marine organisms. In a six‐month marine field test, coatings incorporating Ce‐BTO achieved superior antifouling performance, markedly surpassing a commercial Cu 2 O‐based antifouling paint. By harnessing renewable ocean mechanical energy and green catalytic chemistry, this piezo‐biocatalytic strategy offers a promising and sustainable pathway for next‐generation antifouling technologies.