'Artificial leaf' makes hydrogen from solar cell

MIT professor behind Sun Catalytix shows off research that taps a solar cell to split hydrogen from water--a system that could be used for cheap, clean, distributed energy systems.

Martin LaMonica Former Staff writer, CNET News
Martin LaMonica is a senior writer covering green tech and cutting-edge technologies. He joined CNET in 2002 to cover enterprise IT and Web development and was previously executive editor of IT publication InfoWorld.
Martin LaMonica
2 min read
Making hydrogen gas (the bubbles) from a solar cell in water, a Sun Catalytix prototype.
Making hydrogen gas (the bubbles) from a solar cell in water, a Sun Catalytix prototype. Martin LaMonica/CNET

Drawing from nature, Massachusetts Institute of Technology professor Daniel Nocera thinks he can draw cheap and clean energy from water.

At the National Meeting of the American Chemical Society, Nocera yesterday presented results from research on making an "artificial leaf" to split water to get hydrogen fuel and oxygen. The goal is to use the solar cell to make hydrogen, which would be stored and then used in a fuel cell to make electricity.

"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," Nocera said in a statement.

In 2009, Nocera and others created Sun Catalytix to commercialize his work on relatively cheap catalysts made from nickel and cobalt for a device called an electrolyzer that splits water into hydrogen and oxygen. The company in the fall raised more money from Indian industrial giant Tata.

Using a $4 million grant from the Advanced Research Projects Agency-Energy (ARPA-E), researchers at Sun Catalytix began work on their second-generation product. Rather than use an electrolyzer to make hydrogen, this product would make hydrogen directly from a solar cell. That would mean a renewable source for the hydrogen fuel and electricity.

Until now, research yielded very low efficiencies in converting sunlight to hydrogen using a solar cell. Nocera yesterday said that researchers are optimistic they can boost the efficiency rate and the durability of the material. In the lab, he said that an artificial leaf prototype operated for 45 hours without a degradation in performance.

At the ARPA-E Summit earlier this month where Sun Catalytix showed a prototype of its second-generation product, company executives said the research will take a few years to complete and about three to five years to create a commercial product.