Co-G Material (IMAGE) Brown University Caption Nanoparticles of cobalt attach themselves to a graphene substrate in a single layer. As a catalyst, the cobalt-graphene combination was a little slower getting the oxygen reduction reaction going, but it reduced oxygen faster and lasted longer than platinum-based catalysts. 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.