Physics

Geology

Seawater

Process engineering

Membrane

Pulp and paper industry

Biomass (ecology)

Oceanography

Fouling

Engineering

Composite material

Chemistry

Materials science

Desalination

Polyvinyl alcohol

Wastewater

Environmental science

Chemical engineering

Waste management

Biochemistry

Evaporation

Environmental engineering

Portable water purification

Thermodynamics

Advanced Materials

Solar vapor generation has presented great potential for wastewater treatment and seawater desalination with high energy conversion and utilization efficiency. However, technology gaps still exist for achieving a fast evaporation rate and high quality of water combined with low-cost deployment to provide a sustainable solar-driven water purification system. In this study, a naturally abundant biomass, konjac glucomannan, together with simple-to-fabricate iron-based metal-organic framework-derived photothermal nanoparticles is introduced into the polyvinyl alcohol networks, building hybrid hydrogel evaporators in a cost-effective fashion ($14.9 m-2 of total materials cost). With advantageous features of adequate water transport, effective water activation, and anti-salt-fouling function, the hybrid hydrogel evaporators achieve a high evaporation rate under one sun (1 kW m-2 ) at 3.2 kg m-2 h-1 out of wastewater with wide degrees of acidity and alkalinity (pH 2-14) and high-salinity seawater (up to 330 g kg-1 ). More notably, heavy metal ions are removed effectively by forming hydrogen and chelating bonds with excess hydroxyl groups in the hydrogel. It is anticipated that this study offers new possibilities for a deployable, cost-effective solar water purification system with assured water quality, especially for economically stressed communities.

Biomass‐Derived Hybrid Hydrogel Evaporators for Cost‐Effective Solar Water Purification