Dresden 2017 – wissenschaftliches Programm
CPP 9.8: Vortrag
Montag, 20. März 2017, 17:15–17:30, ZEU 260
Effective work function reduction of practical electrodes using an organometallic dimer — Kouki Akaike1, Marco V. Nardi1, Martin Oehzelt2,1, Johannes Frisch2,1, •Andreas Opitz1, Christos Christodoulou1, Giovanni Ligorio1, Paul Beyer1, Melanie Timpel1, Igor Pis3, Federica Bondino4, Karttikay Moudgil5, Stephen Barlow5, Seth R. Marder5, and Norbert Koch1,2 — 1Humboldt-Universität zu Berlin, Germany — 2Helmholtz-Zentrum Berlin, Germany — 3Elettra-Sincrotrone Trieste, Italy — 4IOM CNR Laboratorio TASC, Italy — 5Georgia Institute of Technology, USA
The control of the cathode work function (WF) is essential to enable efficient electron injection and extraction at organic semiconductor/cathode interfaces in organic electronic devices. Here, ultraviolet photoelectron spectroscopy is used to determine the work function reduction by moderately air-stable pentamethylrhodocene dimer onto various conducting electrodes, by either vacuum deposition or drop casting from solution, to less than 3.6 eV, with 2.7 eV being the lowest attainable value. Electron transfer from the molecule to the respective substrates is responsible for the appreciable WF reduction. Notably, even after air exposure, the WF of the donor-covered electrodes remains below those of typically used clean cathode metals, such as Al and Ag. This demonstrates the ability of the pentamethylrhodocene dimer to reduce the WF for a wide range of electrodes used in all-organic or organic-inorganic hybrid devices.
K. Akaike et al., Adv. Funct. Mater. 26 (2016) 2493-2502.