Details

Autor(en) / Beteiligte

• Henkel, Christian
• Wittmann, Judith E.
• Träg, Johannes
• Will, Johannes
• Stiegler, Lisa M. S.
• Strohriegl, Peter
• Hirsch, Andreas
• Unruh, Tobias
• Zahn, Dirk
• Halik, Marcus
• Guldi, Dirk M.

Titel

Mixed Organic Ligand Shells: Controlling the Nanoparticle Surface Morphology toward Tuning the Optoelectronic Properties

Ist Teil von

• Small (Weinheim an der Bergstrasse, Germany), 2020-01, Vol.16 (2), p.e1903729-n/a

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Precise control over the ratio of perylene bisimide (PBI) monomers and aggregates, immobilized on alumina nanoparticle (NP) surfaces, is demonstrated. Towards this goal, phosphonic acid functionalized PBI derivatives (PA‐PBI) are shown to self‐assemble into stoichiometrically mixed monolayers featuring aliphatic, glycolic, or fluorinated phosphonic acid ligands, serving as imbedding matrix (PA‐M) to afford core–shell NPs. Different but, nevertheless, defined PBI monomer/aggregate composition is achieved by either the variation in the PA‐PBI to PA‐M ratios, or the utilization of different PA‐Ms. Various steady‐state as well as time‐resolved spectroscopy techniques are applied to probe the core–shell NPs with respect to changes in their optical properties upon variations in the shell composition. To this end, the ratio between monomer and excimer‐like emission assists in deriving information on the self‐assembled monolayer composition, local ordering, and corresponding aggregate content. With the help of X‐ray reflectivity measurements, accompanied by molecular dynamics simulations, the built‐up of the particle shells, in general, and the PBI aggregation behavior, in particular, are explored in depth. The optical properties of perylene bisimides (PBI) are strongly aggregation dependent. Thus, PBIs are perfect candidates for probing interdye interactions on top of nanoparticle surfaces. The synergetic interplay of different spectroscopy techniques and molecular dynamics simulations gives deep insights into the formed H‐aggregates. This knowledge is used to fine‐tune the surface morphology of the attached dye molecules.