Bacteria and Nanowires: A Match Made for Space

Nanowires

An article published on, sciencedaily.com, chemists at the University of California- Berkeley, may have found the means to sustain life on Mars and reduce the amount of carbon dioxide in the atmosphere. The rise of carbon dioxide due to the burning of fossil fuels and deforestation has been seen across the globe. With the rise in carbon dioxide in the atmosphere a multitude of results have been yielded. The greenhouse effect, when gases such as carbon dioxide trap the sun’s heat which causes a rise and temperature, but one of these results. The greenhouse effect coupled with deforestation and other forms of pollution are promoting climate change, which has had drastic effects on wildlife and the environment. 

 

Sporomusa ovata

Scientists have created a hybrid (biomechanical) system of bacteria and nanowires that uses solar energy to convert carbon dioxide and water into other organic molecules such as carbohydrates, oxygen, and acetate. The nanowires are thin silicon strands, about one hundred times thinner than a strand of human hair, which are used as the electrical components and solar cells. These scientists have also hit a new milestone and have begun packing bacteria (Sporomusa ovata) in the nanowires. The nanowires conduct the solar energy to the bacteria while the bacteria is able to pull carbon dioxide from the air, add some water and you have a process very similar to photosynthesis. 

At first the efficiency of this method was not the best but, that was soon corrected. The conservation of the solar energy to organic molecules was similar to the efficiency of photosynthesis in plant but drastically low when compared to silicon solar panels. They first tried to just add more bacteria but soon realized that the pH of the surrounding water used for the process increased, this caused the bacteria to separate from the wires and break the circuit. To fix this they found a way to keep the water slightly acidic in order to counteract the continuous acetate production. This also allowed them to pack more bacteria into the nanowires, increasing efficiency by a factor of almost 10, making this more efficient than photosynthesis conducted by most plants. 

With this system able to draw carbon dioxide from the air this could directly address climate change by helping to remove excess carbon dioxide. Scientists also believe that this system could be essential in helping support colonies on Mars. There is expected to be a vast amount of frozen water just beneath the surface of Mars. With this biohybrid system, Mars colonists would have the raw material needed in order to begin the first colonies.