Simple Planar Indium‐Tin‐Oxide‐Free Organic Light‐Emitting Devices with Nearly 39% External Quantum Efficiency

A simple planar indium-tin-oxide-free organic light-emitting device (OLED) with a significantly enhanced external quantum efficiency of nearly 39% is reported. By inserting a high-index layer below the low-index transparent conducting polymer electrode, most optical benefits of the low-index electrode are retained, yet the radiation into the substrate is more convergent within the escape cone for direct optical out-coupling. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.