The process of turning sunlight directly into usable energy - i.e., photosynthesis - may soon be a feat humans are able to mimic to harness the sun's energy for clean, storable, efficient fuel, say the researchers, potentially opening up a whole new frontier of clean energy. Such synthetic photosynthesis - the ability to store the energy easily, without requiring bulky batteries - would dramatically change the renewable energy landscape.
It would avoid the pitfalls of current clean energy technlogies such as wind turbines and photovoltaics, say the researchers, which have downsides in terms of environmental effects and complicating factors.
“We and other researchers around the world are working incredibly hard to try to come up with accessible energy," says Yulia Puskhar, a biophysicist and professor of physics in Purdue’s College of Science. "Energy that is clean and sustainable that we can create with nontoxic, easily available elements. Our artificial photosynthesis is the way forward."
In plants, photosynthesis is a complex set of processes where plants convert the sun's radiance and water molecules into usable energy in the form of glucose. To do this, they use a pigment, usually chlorophyll, as well as proteins, enzymes, and metals.
Compared to photovoltaic technology, where a solar cell converts the sun’s energy into electricity, photosynthesis is radically more efficient, say the researchers. While current photovoltaic technology is only able to capture about 20% of the sun's energy - limited by semiconductors' ability to absorb light energy and by the cell's ability to produce power - photosynthesis is capable of storing 60% of the sun's energy as chemical energy in associated biomolecules.
"With artificial photosynthesis, there are not fundamental physical limitations," says Pushkar. "You can very easily imagine a system that is 60% efficient because we already have a precedent in natural photosynthesis. And if we get very ambitious, we could even envision a system of up to 80% efficiency."
"Photosynthesis is massively efficient