Researchers have developed a filter that can kill bacteria in drinking water using just sunlight and some carbon nanotubes.
The filter, which is described in a paper in npj Clean Water,could become a useful purifier in places without access to reliable drinking water.
The secret ingredient is nanometre-sized wires made from titanium dioxide. When combined with UV light, the nanowires cause small amounts of water (H2O) to react and become chemicals called Reactive Oxygen Species (ROS) – things like hydrogen peroxide (H2O2), hydroxide (OH–) and oxygen (O2–).
While not present in high enough amounts to be a problem for people, these compounds can all wipe out bacteria pretty efficiently.
The researchers, who are based at the Swiss Federal Institute of Technology Lausanne (EPFL), Switzerland, also found that when they combined the titanium dioxide nanowires with carbon nanotubes, the mixed material was even better at removing pathogens.
To read more, click here.