The notion of an artificial leaf makes so much sense because leaves, of course, harness energy from the sun to turn carbon dioxide into the carbohydrates that power a plant’s cellular activities.
For decades, scientists have been working to devise a process similar to photosynthesis to generate a fuel that could be stored for later.
This could solve a major challenge of solar and wind power—providing a way to stow the energy when the sun is not shining and the air is still.
A step closer to actual photosynthesis would be to employ the hydrogen in a reduction reaction that converts CO2 into hydrocarbon, and, like a real leaf, this system would use only CO2, water and sunlight to produce fuels.
In a June 2016 issue of Science, Daniel G. Nocera and Pamela A. Silver, both at Harvard University, and their colleagues reported on an approach to making liquid fuel (specifically fusel alcohols) that far exceeds a natural leaf’s conversion of carbon dioxide to carbohydrates.
The achievement could be revolutionary, enabling creation of a closed system in which carbon dioxide emitted by combustion was transformed back into fuel instead of adding to the greenhouse gases in the atmosphere.