Synergistic Integration of Atmospheric Water Harvesting and Solar‐Driven Hydrogen Production via Multifunctional Hygroscopic‐Photocatalytic Hydrogel Nanocomposite

Abstract The synergistic integration of ambient resource (eg. atmospheric water) utilization and renewable clean energy (eg. hydrogen) conversion presents a transformative pathway toward sustainable clean fuel generation. While atmospheric water extraction coupled with solar‐powered photocatalytic hydrogen production offers a promising alternative to conventional energy systems, its practical implementation remains constrained by persistent water scarcity challenges, particularly in arid regions with high solar insolation. To address this critical limitation, herein, it is presented a kind of multifunctional hygroscopic‐photocatalytic hydrogel nanocomposite engineered for dual functionality: 1) remarkable atmospheric moisture capture (4.49 g g ⁻¹ water uptake capacity) and 2) efficient in situ photocatalytic water splitting ability (17.5 mmol m ⁻² h ⁻¹ hydrogen evolution rate). The rationally designed 3D network structure simultaneously enhances moisture sorption kinetics while mitigating interfacial resistance at the vapor‐photocatalyst interface through optimized proton transport pathways. Notably, the system achieves a record hydrogen yield of 2.70 mmol m ⁻² under natural diurnal cycles without auxiliary energy inputs. This work establishes a paradigm‐shifting approach to sustainable energy‐water nexus management and provides a potential solution for addressing both global water scarcity and clean energy demands, particularly in water‐deficient regions.