Light-driven cation pumping in atomic-level van der Waals heterostructures towards efficient osmotic energy harvesting

(44.5% enhancement) with a total energy conversion efficiency of 29% and stable long-term operation. Robust pumping and power output are further maintained across diverse electrolyte systems and natural seawater. This work establishes cascaded vdW heterostructure membranes as an effective materials platform for optically regulated ion pumps, providing new opportunities for solar-assisted osmotic energy harvesting.