If humans can one day reach Mars, one of the problems that needs to be solved in advance is how to produce essentials such as fuel and drugs, rather than bringing them there themselves,media reported. One way is to collect carbon dioxide from the Martian atmosphere and convert it into a common material for organic compounds. In response, scientists at the University of California, Berkeley, have developed a reactor that can do this by using a mixture of bacteria and a large number of nanowires to convert, and according to them, the conversion is at record levels.
It is understood that the reactor created by the team has a similar premise to the natural process of photosynthesis, in which plants use sunlight to convert carbon dioxide into energy-powered sugars. The system is actually drawn from nature, which relies on water and Sporomusa ovata, which are squeezed in nano-line forests, to drive the transformation.
These silicon nanowires are only one percent the thickness of human hair and are the system’s solar collectors. By absorbing light, producing electrons and passing them on to the bacteria living in them, nanowires provide a chemical process in which bacteria convert carbon dioxide and water into acetate and oxygen.
“These silicon nanowires are essentially like an antenna,” says project leader Peidong Yang. In these silicon nanowires, they produce electrons and supply them to these bacteria. The bacteria then absorb carbon dioxide and react to produce acetate. “
On Mars, acetate molecules can be used as the basis for making organic molecules for fuel, plastics or drugs. At the same time, the released oxygen could be used to help astronauts keep their man-made atmosphere at 21 percent of Earth’s oxygen levels.
In fact, the team showed off their first biomixed reactor five years ago, but at the time the reactor had a solar conversion efficiency of about 0.4%. Although this is comparable to the level of many plants, the team hopes to increase this efficiency to match the best available efficiency by nature, which is 4 to 5 per cent.
While the system’s current prototype requires an external solar panel to provide energy, it is capable of a record 3.6% conversion efficiency.
In the real world, silicon nanowires can be used as solar panels, scientists say. Now they are working to further improve the efficiency of the system and are studying how to use genetically engineered bacteria to produce a wider range of organic compounds.
Yang, the project leader, points out that 96 percent of the Martian atmosphere is carbon dioxide, and that silicon semiconductor nanowires can be reacted by absorbing solar energy and passing them on to bacteria. “For deep space missions, you’re concerned about the weight of the payload, and the advantage of biological systems is that they replicate themselves: you don’t need to send a lot of stuff (to space). That’s why our biomixed version is very attractive. “
In addition to the potential for use in Mars colonization, this biohybrid reactor technology could also be used on Earth to help humans fight climate change by making organic compounds and absorbing carbon dioxide from the atmosphere.
The study was published in Joule.