A bioinspired integrated aerogel evaporator for ultra-high power and sustainable electricity generation

Harvesting and converting energy from natural water cycle into distributed electricity by hydrovoltaic generators (HVGs) offers an effective approach for green and sustainable power supply. However, conventional HVGs primarily depend on the interaction between moving water and hydrophilic functional groups (such as -COOH and -OH), resulting in power output limited to the order of a few μWcm⁻². Inspired by the transpiration of luffa, we construct an integrated evaporation-driven hydrovoltaic generator (I-EHVG). The synergistic effect of biomimetic hydrophilic microporous framework and asymmetric electrode facilitate continuous water transport and directional migration of H⁺ and Al³⁺ ions, enabling efficient and sustainable power generation. Notably, the optimized I-EHVG (2.5 cm in diameter) demonstrates outstanding power density of 877.6 μWcm⁻², achieving a two-order-of-magnitude improvement over conventional HVGs. Moreover, the I-EHVG can directly power electronic devices and its output performance can be substantially enhanced by integrating multiple power generation units. This study establishes a reliable and efficient strategy for fabricating high-performance, sustainable HVGs, paving the pathway for the development of more advanced hydroelectric technologies.