Call it faux-tosynthesis. An MIT research team lead by Daniel Nocera revealed an “artificial leaf” that uses the sun’s rays to produce energy. Developing an energy source modeled on photosynthesis like this has long been a goal of energy science. (We actually highlighted Nocera’s project in the GOOD 100 way back in 2009.)
The basic science sounds simple enough: The sun’s rays split water into hydrogen and oxygen, which can then be recombined in a fuel cell. When they are recombined, energy is created. But constructing these artificial leaves out of stable materials that have reasonably long lifespans and aren’t prohibitively expensive has been an obstacle. The challenge, in other words, is making this faux-tosynthesis practical.
Says Nocera:
A practical artificial leaf has been one of the Holy Grails of science for decades….We believe we have done it. The artificial leaf shows particular promise as an inexpensive source of electricity for homes of the poor in developing countries. Our goal is to make each home its own power station.
Their new leaf utilizes relatively abundant and inexpensive materials—nickel and cobalt—for its catalysts. The leaf itself is described as about the size of a playing card, and in laboratory conditions, it’s proven to generate power continuously for 45 hours without a drop in performance. In theory, with one such leaf and a gallon of water, a typical house could be powered for a day.
Here’s an old Department of Energy video with Nocera about how the process works.
[youtube]https://www.youtube.com/watch?v=WD9yr-Bf-Kw
Right now, Nocera’s leaf is about ten times more efficient than a natural leaf, and his team is working to increase that number. It would need to scale considerably to power American homes, but relatively energy-light homes in the developing world could see the benefits of these solar leaves in the not-too-distant future.
Image: Screenshot from this DOE video
