Researchers have created a water purifier based on optical discs by using the surface of the discs for growing a substrate of zinc oxide nanorods as small as a thousandth the width of a human hair. Zinc oxide combined with ultraviolet light is able to break down organic materials.
The optical discs, like CDs and DVDs, are used as a substrate for the zinc oxide and the researchers from the National Taiwan University, National Applied Research Laboratories and the Research Center for Applied Sciences grew zinc oxide nanorods on the surface of the discs.
The result, a layer of standing rods, is able to break down organic materials when combined with UV light. Optical discs are designed to rotate at high speeds and were therefore found an ideal part of the water purifier. Because the disks are durable and able to spin quickly, contaminated water that drips onto the device spreads out in a thin film that light can easily pass through, speeding up the degradation process.
The water purifier from the Taiwanese researchers measures one cubic foot and consists of a UV light source, a system that recirculates the water to further break down the pollutants and the zinc oxide-coated optical disk.
The researchers claim the device can treat 9 liters of waste water per hour.