Interface studies of intermediate connectors and their roles in tandem OLEDs

Understanding the physical properties of the intermediate connectors in tandem organic light-emitting diodes (OLEDs) is not only important fundamentally, but also crucial to developing high-efficiency tandem organic (opto)electronic devices. Here, the working mechanisms of several effective intermediate connectors in tandem OLEDs using doped or non-doped organic p-n heterojunctions have been systematically investigated by studying the corresponding interfaces and devices. The physical insights provide guidance for identification of new materials and device architectures for high-performance devices.