Turning sunlight into clean water: Stanford scientists unveil groundbreaking, reusable disinfection powder
Access to clean, microbe-free drinking water is a prevalent problem for nearly two billion people worldwide, as highlighted by Stanford University scientists in the US. They have created a cost-effective and non-toxic powder that kills waterborne microorganisms under sunlight. Moreover, the compound can be reused.
2:46 PM EST, January 22, 2024
"Waterborne diseases result in two million deaths annually, primarily affecting children under five," stated Dr. Tong Wu, co-author of the study. "We are hopeful that our innovative technology will initiate transformative changes in water disinfection techniques and stimulate further advancements in this dynamic interdisciplinary field," he added.
The simple method of water disinfection developed by scientists
Earlier methods of water purification primarily involved the use of ultraviolet light and chemical disinfectants, both of which can generate toxic by-products. Moreover, this method is time-consuming and relies on a source of electricity.
Stanford researchers have developed a new, harmless metallic powder for disinfection. This powder functions by absorbing both UV radiation and high-energy visible light from the sun. The powder's composition includes aluminum oxide nanoparticles, molybdenum sulfide, copper, and iron oxide.
"We have used just a small quantity of these materials," remarked Professor Yi Cui, the senior author of the study. "When immersed in water, they function in harmony. The tiny powder particles can move swiftly and physically contact multiple bacteria, eliminating them rapidly," he added.
The water disinfecting powder is reusable
This innovative powder is combined with bacteria-infected water. The mixture is then exposed to sunlight, which quickly kills the bacteria. Following disinfection, the metallic powder can be collected using a magnet for subsequent use.
"I envision hikers carrying a small quantity of this powder and a magnet," suggested Cui. "Throughout the day, sprinkle the powder in the water, mildly shake it in the sunlight and within a minute, you have potable water. A magnet can be used to separate the particles for later use," he explained further.
Professor Cui suggested that the powder could also be used in wastewater treatment centers where UV lamps are currently used for disinfecting treated water.