A seawater desalination facility that PUB (Public Utilities Board) of Singapore starts operating on Jurong Island in April 2022; it is Singapore's fifth seawater desalination facility. /Courtesy of PUB

A domestic research team has developed a technology that can convert seawater into drinking water faster than existing methods. Expectations are rising that it could offer a clue to solving the global "water shortage" problem.

Pohang University of Science and Technology (POSTECH) said on the 14th that Professor Lee Sang-jun of the Department of Mechanical Engineering and a team led by Dr. Higgins Wilson recently published a desalination technology that delivers stable performance regardless of weather or time of day in the international engineering journal Communications Engineering.

Until now, researchers have focused on "interfacial evaporation," a technique that uses solar heat to selectively heat only the water at the water–air interface. While this method has the advantage of fast evaporation, its performance has fluctuated with weather and day–night changes.

To overcome this, the team introduced a "Joule heating" method that uses low-voltage electricity (5V or less). It harnesses the heat generated as electricity flows, similar to how an electric heating mat warms up.

As a material, they used "glassy carbon foam," which has densely packed pores. This material is lightweight, strong, and stable even at high temperatures. The team coated it with a chemical called "thiol" to enhance water absorption and lowered the electrical resistance to improve conductivity.

A schematic of the interfacial evaporator that researchers improve with the new technology. /Courtesy of Pohang University of Science and Technology POSTECH

The results were striking. In experiments evaporating pure water, the evaporator surface temperature rose rapidly to 98°C, evaporating 205 kg/㎡ of moisture per hour. This exceeds twice the previous world record. Even with seawater at a concentration of 3.5%, it processed 18 kg/㎡ per hour, demonstrating unprecedented desalination performance.

Lee said, "This study is an innovation that surpasses the limits of conventional interfacial-evaporation desalination technology," adding, "The rapid high-temperature heating technology can be applied not only to desalination but also to various fields such as sterilization and atmospheric water vapor capture."

References

Communications Engineering (2025), DOI: https://doi.org/10.1038/s44172-025-00498-z

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