Scientists from Harvard University in the US have developed a bionic 'leaf' that uses solar energy to turn carbon dioxide into liquid fuel.
The 'leaf' combines an artificial catalyst, which uses electricity to split hydrogen gas from water, and a soil bacterium, which uses the hydrogen as fuel to build new molecules with carbon.
The resultant compound, isopropanol, is an industrial alcohol that can be used like gasoline or ethanol. The compound could be a carbon-neutral fuel – perfect for a world designed around liquid fuels.
Microbes have an "unprecedented ability" to turn incoming energy into useful molecules, according to the team. In the future, the same principles could be applied to produce other useful molecules such as food and even drugs.
The next step is to make the system more efficient – the team is aiming to turn 5% of the solar energy received into fuel.