Ionic Junction (IMAGE) Cornell University Caption Schematic of a junction between two organic semiconductors, an anthracene derivative containing free positive ions and a ruthenium, complex containing negative ions. When the two are joined, ions diffuse across the junction creating a difference in energy levels that facilitates rectification, electroluminiscence and photovoltaic response. For experimental purposes the materials were sandwiched between electrodes made of gold and indium tin oxide. The latter is transparent. Credit Malliaras lab/Cornell 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.