A research team led by Associate Professor Luat Vuong at UC Riverside discovered that ultraviolet (UV) light around 200 nm can directly target salt-water bonds, offering a potential alternative to the traditional method of heating water for evaporation, tells Tech Xplore. Their experiments used a white ceramic wick made of aluminum nitride (AlN-OH) in a controlled chamber; under deep-UV exposure, salt-water evaporation increased significantly compared with red, yellow, or infrared light.
Unlike standard solar desalination, which uses dark materials to absorb sunlight, boil water, and condense steam, this method could bypass bulk heating. The AlN wick exploits photon up‐conversion, a mechanism where lower-energy photons combine to form higher-energy ones strong enough to break salt‐water bonds. The advantages of AlN include low cost, wide availability, hydrophilicity, and durability.
The potential impact is substantial: by avoiding the energy-intensive boiling or high-pressure membranes used in typical systems, this technique could reduce electrical load and brine discharge challenges, improving sustainability. However, the team emphasizes that this remains at the laboratory stage. Questions remain around scalability, real-world efficiency, system integration, and long-term durability.
For engineers and designers focused on water systems and sustainability, this work suggests a new material-and-spectra paradigm in desalination: think photon-based separation rather than just thermally driven evaporation or high-pressure filtration. The approach invites revisiting system architecture from materials selection and light management to integration with solar infrastructure and low-energy deployment in remote or off-grid settings.
This deep-UV mechanism points toward a promising direction in desalination, one that could shift the design focus from heat and pressure toward spectral control and material engineering.