An “artificial leaf” developed by researchers at Harvard University is able to turn solar energy into liquid fuels, a recent study in the journal Science reports.
This technology, which builds on past research, has been a work in progress for many years. While the first versions of the leaf were effective, they could not overcome certain obstacles, such as creating reactive oxygen species that destroyed the hydrogen-eating bacteria’s DNA.
The first model also used a nickel-molybdenum-zinc alloy hydrogen-producing catalyst, which was essential for the leaf to run on high voltage. However, that caused the technology to have a low-efficiency rate. Even so, early versions of the leaf were able to use solar energy to produce isopropanol, a liquid alcohol used in the production of many commercial products.
The new version of the leaf creates energy by dividing both hydrogen-eating bacteria and water molecules. It has a cobalt-phosphorous alloy catalyst and does not produce reactive oxygen species. As a result, it can run on low voltage, greatly increasing its efficiency, Tech Times reports.
The leaf transforms solar energy into biomass with a 10 percent efficiency rate. In comparison, the fastest growing plant species has a conversion rate of only one percent. The process works just like photosynthesis, but the end result is fuel rather than just energy.
“This is a true artificial photosynthesis system,” said Daniel Nocera, the Patterson Rockwood Professor of Energy at Harvard University and co-creator of the system, in a statement. “Before, people were using artificial photosynthesis for water-splitting, but this is a true A-to-Z system, and we’ve gone well over the efficiency of photosynthesis in nature.”
The leaf also can create isopentanol, isobutanol, and a bio-plastic precursor called PHB. In fact, the device could be used to create any downstream carbon-based molecule. It also contains a self-healing system that prevents leaking into the finished solution.
The bionic leaf has many potential commercial applications, such as powering cars or creating cosmetics. The researchers also note that poorer nations that could benefit from a cheap, easy way to create energy.
“It’s an important discovery — it says we can do better than photosynthesis. But I also want to bring this technology to the developing world as well,” added Nocera.