Starfish-inspired magnetoelastic generator array for ocean wave energy harvesting

Abstract

The direction and frequency drift of ocean waves presents considerable challenges to existing platform technologies to utilize such energy. Here, we present a starfish-inspired magnetoelastic generator (MEG) array floating on the ocean surface, efficiently converting irregular ocean wave fluctuations into electricity for sustainable water splitting and hydrogen (H₂) fuel production. Within the starfish-inspired MEG array system, each MEG unit that harnesses the magnetoelastic effect to efficiently convert local ocean wave energy into electricity with a voltage of 12.52 mV cm⁻² and a current of 0.24 mA cm⁻² at 2 Hz. By integrating eight such units onto the tube feet, the starfish-inspired system achieved a maximum peak voltage of 4.33 V, charged a capacitor to 2.42 V within 80 s and electrolyzed the water to continuously produce H₂ at a rate of 1.18 μL min⁻¹. The starfish-inspired MEG array is a milestone for ocean wave energy harvesting, promoting H₂ economics and carbon neutrality.