Pentacene/perfluoropentacene bilayers on Au(111) and Cu(111): impact of organic–metal coupling strength on molecular structure formation

DOI: 10.1039/D1NA00040C

Authors: Qi Wang (Universität Tübingen; Soochow University) , Jiacheng Yang (Soochow University) , Antoni Franco-Canellas (Universität Tübingen) , Christoph Buerker (Universität Tübingen) , Jens Niederhausen (Helmholtz Zentrum Berlin für Materialien und Energie) , Pierre Dombrowski (Philipps-Universität Marburg) , Felix Widdascheck (Philipps-Universität Marburg) , Tobias Breuer (Philipps-Universität Marburg) , Gregor Witte (Philipps-Universität Marburg) , Alexander Gerlach (Universität Tübingen) , Steffen Duhm (Soochow University) , Frank Schreiber (Universität Tübingen)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nanoscale Advances , VOL 28

State: Published (Approved)
Published: March 2021
Diamond Proposal Number(s): 18860

Abstract: As crucial element in organic opto-electronic devices, heterostructures are of pivotal importance. In this context, a comprehensive study of the properties on a simplified model system of a donor–acceptor (D–A) bilayer structure is presented, using ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED) and normal-incidence X-ray standing wave (NIXSW) measurements. Pentacene (PEN) as donor and perfluoropentacene (PFP) as acceptor material are chosen to produce bilayer structures on Au(111) and Cu(111) by sequential monolayer deposition of the two materials. By comparing the adsorption behavior of PEN/PFP bilayers on such weakly and strongly interacting substrates, it is found that: (i) the adsorption distance of the first layer (PEN or PFP) indicates physisorption on Au(111), (ii) the characteristics of the bilayer structure on Au(111) are (almost) independent of the deposition sequence, and hence, (iii) in both cases a mixed bilayer is formed on the Au substrate. This is in striking contrast to PFP/PEN bilayers on Cu(111), where strong chemisorption pins PEN molecules to the metal surface and no intermixing is induced by subsequent PFP deposition. The results illustrate the strong tendency of PEN and PFP molecules to mix, which has important implications for the fabrication of PEN/PFP heterojunctions.

Subject Areas: Materials, Chemistry


Instruments: I09-Surface and Interface Structural Analysis

Other Facilities: ID32 at ESRF

Documents:
d1na00040c.pdf

Discipline Tags:

Organic Chemistry Material Sciences Chemistry

Technical Tags:

Diffraction Spectroscopy X-ray Standing Wave (XSW) X-ray Photoelectron Spectroscopy (XPS)