Solar-powered
interfacial evaporation has emerged as an innovative
and sustainable technology for clean water production. However, the
rapid, mass and shape-controlled fabrication of three-dimensional
(3D) steam generators (SGs) for versatile hybrid applications remains
challenging. Herein, composite aerogel beads with self-contained properties
(i.e., hydrophilic, porous, photothermal, and durable) are developed
and demonstrated for threefold hybrid applications including efficient
solar-powered interfacial evaporation, water remediation, and controlled
soil enrichment. The rational incorporation of selected polysaccharides
enables us to fabricate bead-like aerogels with rapid gelation, continuous
processing, and enhanced ion adsorption. The composite beads can attain
a high water evaporation rate of 1.62 kg m–2 h–1 under 1 sun. Meanwhile, high phosphate adsorption
capacity of over 120 mg g–1 is achieved in broad
pH (2.5–12.4) and concentration (200–1000 mg L–1) ranges of phosphate solutions. Gratifyingly, we demonstrate the
first example of recycling biomaterials from interfacial SGs for controlled
nutrient release, soil enrichment, and sustainable agriculture. The
phosphate-saturated beads can be gradually broken down in the soil.
Macronutrients (N, P, and K) can be slowly released in 50 days, sustaining
the plant germination and growth in a whole growth stage. This work
shines light on the mass and controlled fabrication of aerogel beads
based on double-network biopolymers, not merely scaling up solar-powered
interfacial evaporation but also considering water remediation, waste
material disposal, and value-added conversion.