As the name suggests, GraphAir isn’t manufactured in the conventional way, using high temperatures, high pressures, and long timescales. Instead, the researchers managed to find a way to make it using the humble soybean. Specifically, soybean oil: when heated, it disseminates into carbon units that can form single-to-multilayer graphene film in just a single step.
Using ambient air – hence the name – this process means graphene can be produced very cheaply, so that’s that problem solved. As a bonus, a variety of similar materials, including oil left over from barbeques, works just as well as soybean gloop, which means this mechanism is also relatively eco-friendly.
Graphene, frustratingly, is hydrophobic, which means it normally repels water. In order to circumvent this problem, the team added some microscopic channels, which allowed the water to pass through, but which prevented pollutants and salt, which are far larger molecules, from going with it.
Alone, a typical water filtration mechanism gets clogged up by these pollutants over time, and requires cleaning, and often a more complex, pricier device that segregates two types of filters. When overlaid with a GraphAir filter, however, the team found that not only were 99 percent of contaminants filtered out at twice the rate of the ordinary filter alone, but clogging never became an issue.
So, although it’s early days, the team have essentially concocted a cheap, effective, simple water filtration design. We doubt those 2.1 billion people would be disinterested in this kind of success.