Dichtel -- COF3 (IMAGE) Northwestern University Caption Covalent organic frameworks (COFs) offer a unique combination of properties that show promise for water purification, energy storage and electronic devices. Credit Northwestern University Usage Restrictions Credit must be given 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.