Solar‐Powered Rotary Water Harvesting System for Continuous Hydrogen Generation

Abstract

Water scarcity poses a critical challenge to sustainable hydrogen (H2) production via electrolysis. Here, we present a solar‐driven, rotary sorption‐based atmospheric water harvesting (SAWH) system integrated with an electrolytic cell for decentralized H2 generation. The core of the device is a hygroscopic porous gel (HSN–Li) featuring interconnected channels and photothermal TiN nanoparticles, enabling rapid sorption/desorption kinetics and high water uptake performance (up to 2.62 gwater gsorbent−1 at 25°C and 60% RH). Coupled with a Janus membrane modified electrode, the system achieves efficient bubble detachment and continuous H2 evolution. Under outdoor conditions, the prototype delivers a water yield of 1.55‐2.1 Lwater kgsorbent−1 day−1 and an ultrafast H2 production rate of 8.4 L m−2 h−1, powered entirely by solar energy. This multifunctional platform eliminates dependence on liquid water, offering a scalable, low‐cost route for H2 generation in water‐stressed regions. Our approach establishes a new paradigm for integrated water harvesting and green energy production, paving the way for sustainable H2 technologies.