Integrating Rooftop Agriculture and Atmospheric Water Harvesting for Water‐Food Production Based on Hygroscopic Manganese Complex

Abstract

AbstractThe integration of atmospheric water harvesting and rooftop agriculture presents a promising solution for decentralized water and food supply in urban areas. However, the degradation of adsorption material kinetics after scaling up, coupled with fluctuations in solar energy, results in reduced and unstable water production. Herein, a composite adsorbent composed of manganese (II)‐ethanolamine complexes incorporated into a hierarchical and interconnect polypyrrole‐doped matrix is developed. This structure significantly reduces vapor diffusion resistance—a crucial factor impeding rapid scale‐up kinetics, enabling water uptake of 2.54 g g−1 at 90% RH, with 62% of water released within 30 min, facilitating daily multiple capture‐release cycles. Incorporating a hybrid desorption mode that combines PV electrical and solar heating further achieves stable and high‐yield water production. Ultimately, through simulation and feasibility verification, the atmospheric water‐irrigated rooftop farm realizes water and food production yield of 879.9 gwater m−2sorbent day−1 and 1.28 kgfood m−2device within 14 days without human intervention and independent of external water inputs. These findings highlight the potential of integrating AWH technology with rooftop farming as a pathway to sustainable urban development through decentralized water and food co‐production.