QAZAQ GREEN.  Researchers from the Institute of Process Engineering of the Chinese Academy of Sciences and Shenzhen University have developed a new three-dimensional photothermal structure that significantly boosts solar water evaporation efficiency, offering a potential solution to freshwater shortages in remote and arid regions.

The new material integrates polymer chains with hollow multishelled structures, achieving a record evaporation rate of 38.14 kg per square metre per hour — 8.5 times higher than previously reported two-dimensional membrane systems. The study was published in Advanced Materials on June 21.

According to Prof. Wang Dan, the corresponding author, the material's unique "nanoforest" microstructure maximises sunlight capture, while the nanoconfinement effect reduces evaporation energy consumption by 45.7%. Durability tests showed no detectable particle detachment after 30 days of continuous seawater exposure, and no active free radicals were detected under light exposure, indicating strong long-term reliability.

Field tests using a 0.75-square-metre outdoor device operating under natural sunlight produced 20.16 litres of freshwater per day — enough to meet the basic drinking needs of around ten people — with water quality meeting World Health Organization standards.

The desalinated water was also used to irrigate a 5-square-metre experimental plot, successfully supporting the full growth cycle of spinach, corn and Chinese cabbage, demonstrating the technology's potential for agricultural use in water-scarce areas.

The researchers estimate that after two years of operation, the cost of water produced by the system would fall below that of commercial bottled water, suggesting strong economic viability for long-term deployment in regions facing chronic water shortages.