Interlocking Stabilized 3D Photothermal Nano-Architectures Enables Distributed Solar Desalination

Area of Science:

• Materials Science and Engineering
• Sustainable Energy Technologies
• Environmental Science and Engineering

Background:

• Global water scarcity necessitates sustainable solutions at the water-energy-food nexus.
• Solar-driven evaporation is a promising desalination method but faces challenges in performance, durability, and cost.
• Integrating efficient photothermal materials is crucial for practical solar desalination.

Purpose of the Study:

• To develop a scalable and economical strategy for constructing 3D photothermal architectures.
• To enhance solar absorption and evaporation efficiency for water desalination.
• To demonstrate the practical application of the developed material in producing freshwater and supporting agriculture.

Main Methods:

• Utilized hollow multishelled structures (HoMS) and interlocking polymer molecular chains to create 3D photothermal architectures.
• Employed Hansen solubility parameters for precise polymer threading and uniform nanomaterial loading, forming a hierarchical 'nanoforest' morphology.
• Integrated the material into an active-condensation solar desalination device and conducted crop growth experiments.

Main Results:

• Achieved 90.2% broadband solar absorption and a 45.7% reduction in evaporation energy consumption.
• Reached a record high evaporation rate of 38.14 ± 0.57 kg m⁻² h⁻¹ with year-long stability.
• Produced 20.16 L of WHO-standard freshwater per day from a 0.75 m² device and supported crop growth over 5 m².

Conclusions:

• The developed HoMS-based photothermal material offers a feasible and sustainable route for solar-driven water desalination.
• The hierarchical 'nanoforest' structure enhances solar absorption and evaporation efficiency.
• This technology effectively addresses water scarcity by providing clean water and supporting agricultural needs at a lower cost.