Carbon (IMAGE) University of Cincinnati Caption University of Cincinnati chemical engineering student Tianyu Zhang holds up a vial of graphene used as a catalyst to convert carbon dioxide into methane. Credit Andrew Higley/UC Creative Usage Restrictions None License Original 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.