E-Mail IMAGE: Guosong Zeng, a postdoctoral scholar in Berkeley Lab's Chemical Sciences Division, at work testing an artificial photosynthesis device made of gallium nitride. Zeng, along with Berkeley Lab staff scientist Francesca... view more Credit: Thor Swift/Berkeley Lab Three years ago, scientists at the University of Michigan discovered an artificial photosynthesis device made of silicon and gallium nitride (Si/GaN) that harnesses sunlight into carbon-free hydrogen for fuel cells with twice the efficiency and stability of some previous technologies. Now, scientists at the Department of Energy's (DOE's) Lawrence Berkeley National Laboratory (Berkeley Lab) - in collaboration with the University of Michigan and Lawrence Livermore National Laboratory (LLNL) - have uncovered a surprising, self-improving property in Si/GaN that contributes to the material's highly efficient and stable performance in converting light and water into carbon-free hydrogen. Their findings, reported in the journal