Biomimcry > Researchers create synthetic porphyrins, that mimic plant photosynthesis efficiently harvesting energy from light
Re-inventing nature for cheaper solar power
Many research groups around the world are tackling this problem, but a research team in Sydney has created molecules that mimic those in plants which can efficiently harvest energy from light and power life on Earth.
“A leaf is an amazingly cheap and efficient solar cell,” says Dr Deanna D’Alessandro, a postdoctoral researcher in the Molecular Electronics Group at the University of Sydney. “The best leaves can harvest 30 to 40 percent of the light falling on them. The best solar cells we can build are between 15 and 20 percent efficient, and expensive to make.”
“We’ve recreated some of the key systems that plants use in photosynthesis,” says Deanna.
Bacteria and green plants use photosynthesis to convert light energy into usable chemical energy. Wheel-shaped arrays of molecules called porphyrins collect light and transfer it to the hub where chemical reactions use the light energy to convert carbon dioxide into energy-rich sugar and oxygen.
“This process, which occurs in about 40 trillionths of a second is fundamental to photosynthesis and is at the base of the food chain for almost all life on Earth,” says Deanna.
“We have been able to construct synthetic porphyrins. More than 100 of them can be assembled around a tree-like core called a dendrimer to mimic the wheel-shaped arrangement in natural photosynthetic systems.”
These molecules designed by the team are about 1 billionth the size of a soccer ball. But the large number of porphyrins in a single molecule means that a significant amount of light can be captured and converted to electrical energy – just like in nature.
“Since they are so efficient at storing energy, we think they could also be used as batteries – replacing the metal-based batteries that our high technology devices depend on today,” Deanna says.
“Our preliminary results are very promising. We are still in the early stages of building practical solar energy devices using our molecules,” said Deanna. “The challenge is immense, but is crucial to providing alternative energy solutions for Australia and the world.”
Now they’ve made the molecules, the team along with their Japanese collaborators at Osaka University are working to combine them in the equivalent of a plant cell.
ETA 2011
Then, over the next five years they will attempt to scale up the technology to commercial scale solar panels.
Key concepts & New Buzz words to learn and remember
Porphyrins, dendrymirs, Artificial Photosynthesis (AP)
On the way out -what could get obscoleced?
Conventional lead battery
Silicon-based solar cells
Source: Science in Public and Physorg.com
It certainly is fantastic science. Whats more these chemicals are beautiful.I used to work with the very compounds deanna has been promoting. However, one must not swallow this PR stuff comming out of universities with too many grains of salt. The simple and rather depressing realities are that the commercial manufacture of these devices is prohibitivley expensive and will be for,..well forever..as far as you and I are concerned. The chemistry is just not able to be 'industrialised'. also, these things are models, they are unstable (to light no less!!) they make interesting reading in the scientific literature and I dont deny that basic science like this is pricless in terms of generating new technologies. what rubs me the wrong way is this scientific newsflash makes it sound like something actually is going to happen, and come out of this research. Research publicity like this is done for the simple reason of gaining accolades for the ambitious and grant money for the sqweaky wheels. uni of syd is full of such self congratulations.
Im sorry to be a wet blanket but science is about truth, PR is most certainly NOT.
Posted by: disillusioned | January 17, 2007 at 10:53 PM