World’s fastest solar evaporator makes 1 gallon of fresh water an hour

Scientists at Korea’s Ulsan National Institute of Science and Technology (UNIST) have developed the world’s fastest oxide-based solar evaporator capable of producing about 1.4 gallons (4.1 liters) of fresh water per hour from seawater without using electricity. This innovation addresses the energy-intensive nature of desalination by harnessing sunlight through a novel photothermal material made from a ternary oxide. By substituting parts of manganese oxide with copper and chromium and employing bandgap engineering, the material absorbs nearly 97% of sunlight across ultraviolet to near-infrared wavelengths, significantly increasing heat generation and surface temperatures up to 176°F (80°C), surpassing previous materials. To tackle the common issue of salt buildup on the evaporator’s surface, the researchers designed an inverted U-shaped device incorporating water-wicking fibers and hydrophobic polyester fabric. This design facilitates continuous water flow and salt ion removal, preventing salt accumulation that typically hampers solar desalination efficiency. The scalable and durable evapor