Two point two billion people lack safe drinking water. Desalination plants dot coastlines from California to the Middle East. Yet the process remains costly, energy hungry and dirty. It spits out brine that harms ocean life. Chemicals treat the water before and after. Scale builds up and shuts systems down. That may change. Engineers at the University of Rochester built a solar panel that pulls fresh water from the sea. No added chemicals. No liquid waste. Salts come out as solids. Some of those solids carry lithium for batteries. The work appeared May 27 in Light: Science & Applications . Chunlei Guo led the project. He serves as professor of optics and physics and senior scientist at the university’s Laboratory for Laser Energetics. His team textured sheets of black metal with femtosecond lasers. The treatment creates a surface that drinks in nearly all sunlight. It also turns superwicking. Seawater spreads across it in a thin film. Sunlight hits. Water evaporates. Vapor condenses into clean liquid.…