Guosong Zeng testing (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption 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 Toma, discovered that the device improves with use. Credit Thor Swift/Berkeley Lab Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.