Dresden 2020 – scientific programme

The DPG Spring Meeting in Dresden had to be cancelled! Read more ...

Parts | Days | Selection | Search | Updates | Downloads | Help

DS: Fachverband Dünne Schichten

DS 15: Organic Thin Films, Organic-Inorganic Interfaces I (joint session DS/CPP)

DS 15.6: Talk

Tuesday, March 17, 2020, 10:45–11:00, CHE 91

Extended Interphase Formation at a Metal/Organic Interface: Lithium on Tetraphenylporphyrin — •Stefan Renato Kachel, Maik Schöniger, Jan Herritsch, Philipp Schröder, Mark Hutter, and J. Michael Gottfried — Fachbereich Chemie, Philipps-Universität Marburg, Germany

Porphyrins are versatile model compounds for organic semiconductors (OSC) in application-related studies of metal/organic interfaces. The properties of such interfaces strongly influence the performance of organic electronic devices. To study processes at the interface between an OSC and a low work-function metal, lithium was deposited onto tetraphenylporphyrin (H2TPP) layers and the product composition was analyzed with temperature-programmed desorption mass spectrometry (TPD-MS) and X-ray photoelectron spectroscopy (XPS). With sufficient amounts of Li, we found complete conversion of H2TPP into dilithium tetraphenylporphyrin (Li2TPP). The depth range of this reaction exceeds several 10 nm, contrasting previous findings for transition metals. Even a 50 nm thick layer of H2TPP fully reacted with an excess of Li. For substoichiometric amounts of Li, singly metalated LiHTPP was found. This study shows that the metal/organic interface can be very diffuse with a thick reacted interphase layer separating the metal from the pristine OSC.