The Polymer Society of Korea

Abstract

To address the escalating need for carbon-neutral technologies, we introduce a sustainable hydrovoltaic electricity generator that utilizes natural seaweed as the primary functional material. The device operates by converting water evaporation into electricity, driven by a humidity gradient between a copper plate (bottom electrode) and a copper mesh (top electrode). A compact unit (2 cm × 5 cm × 0.1 cm) achieves stable performance under 70% relative humidity, generating an open-circuit voltage of 0.35 V, a current density of 30 μA/cm³, and a power density of 2.64 μW/cm³. When multiple units are connected in series, the system produces sufficient output to drive practical devices such as light-emitting diodes or charge supercapacitors. These results highlight the potential of seaweed-based hydrovoltaics as a scalable, eco-friendly platform for low-power energy harvesting, with biodegradable components and a significantly reduced life-cycle carbon footprint.