Researchers at the University of Surrey in the UK have developed an oxygen-producing, carbon dioxide-absorbing water-based paint containing a species of cyanobacteria, dubbed green living paint.

Cyanobacteria are also called blue-green algae and are increasingly studied as a component for new, green materials, thanks to their highly-efficient photosynthetic properties (turning carbon dioxide into oxygen).

For the paint, the researchers used a type of cyanobacteria called Chroococcidiopsis cubana, which is usually found in the desert. The bacteria require very little water and can survive in extreme environments, leading the researchers to think the coating might be used in space.

To make the paint, the researchers immobilised the bacteria in a mechanically robust biocoating made from polymer particles in water, which was fully dried before rehydrating. They observed that the bacteria within the biocoating produced up to 0.4 g of oxygen per gram of biomass per day and captured CO2. Continuous measurements of oxygen showed no signs of decreasing activity over a month.

Image: University of Surrey