With a little help from bacteria, you can simply charge your smartwatch with indoor or outdoor air.
That remarkable future scenario unfolds as you delve into the paper recently published in the journal Nature . In the article, researchers report that they have found a way to generate electricity using moisture that is simply in the air. It is a completely new technology that has numerous implications and is made possible in part by the very special bacteria Geobacter . The microorganism naturally creates conductive nanowires that the researchers use to generate electricity seemingly from scratch.
It was Lovley himself who discovered the Geobacter microbe in the mud of the Potomac River more than thirty years ago. And by now we know that the bacteria is anything but rare. “Geobacter is a common inhabitant of soil and sediments,” said Lovley. “Like many other bacteria, the bacterium is rod-shaped, but produces electrically charged protein nanowires.” These nanowires enable the bacteria to make unique contact with the environment. And researchers also see other possibilities for those nanowires …
How does it work?
First of all, the nanowires that Geobacter makes are taken from the bacteria. “So there are no further bacterial cells involved,” researcher Derek Lovley tells Scientias.nl . Many of these nanowires are then placed on an electrode as an ultra-thin layer of material. “And a smaller electrode is placed on the nanowires. The nanowires then absorb moisture that is in the air (and naturally has a charge, ed.). The top side of the nanowires layer becomes wetter than the bottom side, as a result of which there is a charging development in the nanowires layer and thus a difference in voltage between the two electrodes. Continuous exposure to the air is necessary to generate power. ”
The researchers have given their special generator the name Air gene. For now it is only a small generator that can also supply very modest amounts of electricity. “The generator can only power small electronic devices,” Lovley says. “The fact that the generator is so small is due to our limited stock of nanowires. It is difficult to cultivate large quantities of Geobacter . ” Fortunately, Lovley and colleagues have come up with something for that. “We recently solved this problem by genetically modifying an E. coli strain (a bacteria that is easy to grow, ed.) To generate nanowires. Now that we have more nanowires, we can make the devices larger and therefore generate more electricity. ”
In the desert
In addition to sufficient nanowires, the generator also needs moisture. But not so much, Lovley emphasizes. As a result, it also works indoors and even in the desert. “The humidity inside and even in the desert is large enough to run the generator.”
The possibilities for Air-gen are endless. For example, researchers see it as a great solution for charging small electronic devices, such as a smartwatch. For example, they are already thinking of developing an Air-gen sticker that you can simply stick on the device and then continuously supply the device with energy. But scaling up the technology also offers opportunities. “The ultimate goal is to make large-scale systems,” says researcher Jun Yao. “For example, the technology can be incorporated into wall paint that provides your home with energy. Or we develop stand -alone air-powered generators that are off-the-gridprovide electricity. As soon as we can make the wires on an industrial scale, I absolutely expect to be able to build large systems that make a huge contribution to sustainable energy production. ”