New solar desalination device makes 3.4 liters of drinking water hourly

Researchers at Ulsan National Institute of Science & Technology (UNIST) have developed an innovative solar desalination device that produces clean drinking water by harnessing sunlight to evaporate seawater without relying on external electricity. Central to this technology is the use of La0.7Sr0.3MnO3, an oxide perovskite material that efficiently converts solar energy into heat through intra-band trap states, facilitating non-radiative recombination of photoexcited electrons and holes. This material, combined with a novel inverse-L-shaped device design that enables one-directional fluid flow, effectively prevents salt accumulation by pushing salt to the edges of the photothermal surface, thereby reducing fouling and light blockage. The system achieves a remarkable solar evaporation rate of 3.40 kg/m²/h (approximately 3.4 liters per hour), significantly outperforming typical rates of 0.3–0.4 kg/m²/h under natural sunlight. Durability tests confirmed stable operation over two weeks