Composite Catalyst (IMAGE) Brown University Caption This is nitrogen-rich graphene festooned with finely tuned copper nanoparticles selectively converts carbon dioxide to ethylene, a key commodity chemical. Credit Sun Lab / Brown University 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.