Hydrogen fuel through artificial photosynthesis

By Brogan Adams

What Is It
A new, stable artificial photosynthesis device doubles the efficiency of harnessing sunlight to break apart both fresh and salt water, generating hydrogen that can then be used in fuel cells. The device could also be made to turn carbon dioxide back into fuel.
How it works
     "If we can directly store solar energy as a chemical fuel, like what nature does with photosynthesis, we could solve a fundamental challenge of renewable energy," said Zetian Mi, a professor of electrical and computer engineering at the University of Michigan 
   When this specially engineered wafer is hit by photons, the electric field helps separate photo-generated electrons and holes to drive the production of hydrogen and oxygen molecules efficiently

The colorized electron microscope image shows the gallium nitride towers of the artificial photosynthesis device at 52.5k magnification.

Plans for the future

    "Although the 3 percent efficiency might seem low, when put in the context of the 40 years of research on this process, it's actually a big breakthrough," Mi said. "Natural photosynthesis, depending how you calculate it, has an efficiency of about 0.6 percent." He says 5% efficiency is the threshold for commercialization but they are aiming for larger amounts, up around 20-30% efficiency. 

   Mi conducts similar research to strip carbon dioxide of its oxygen to turn the resulting carbon into hydrocarbons, such as methanol and syngas. This research path could potentially remove carbon dioxide from the atmosphere, like plants do.

Hydrogen fuel through artificial photosynthesis