Researchers from RMIT and UNSW have recently discovered revolutionary and an inexpensive way for making filters, which are capable of transmuting contaminated water into safe drinking water with the use of heavy metals. These researchers have found and demonstrated that aluminum oxide sheets based nano filters can be produced with relatively lower costs by using virtually zero energy from certain fixed amount of the liquid metal gallium.
Adding a chunk of aluminum to the liquid gallium’s core at room temperature can quickly produce layers of aluminum oxide at the gallium’s surface. The researchers have discovered that aluminum oxide nano-sheets are highly porous, and took efforts to prove suitability of these sheets in filtering oil contamination as well as heavy metal ions at ultra-fast, unprecedented rates. Portable and low-cost filters manufactured by using the liquid metal-based production process could offer people with limited or no access to safe & clean drinking water. This process holds potential in removing toxic substances such as lead in just few minutes.
As lead and various other heavy metals have very high affinity to the aluminum oxide, each of these ions adhere to the aluminum oxide sheets while water passes via billions of layers. At the same time, use of the aluminum oxide sheets is quite safe even with repeated use, as water flow would not be able to detach heavy metal ions from aluminum oxide. Until recently, aluminum had to be processed at over 1000 degrees, or had to undergo other energy-intensive processes, for the production of aluminum oxide. However, with the help of the liquid gallium-based production, aluminum oxide filters can now be manufactured at a cost of as low as 10 cents, thereby making the process attractive for perspective manufacturers.
This methods developed by RMIT and UNSW researches can be leveraged for developing nano-structured materials as nano-fibers and ultra-thin sheets, which differ in innate attributes. The ultra-thin sheets possess high mechanical stiffness, whereas the nano-fibers are very translucent. This ability to produce materials having differential attributes that pave opportunities to tailor shapes for enhancing different properties specific to applications in optics, catalysis, membranes, and electronics. The research is funded by Australian Research Council Center for Future Low-Energy Electronics Technology (FLEET).