Project summaries of area B
The research area B explores new chemical pathways based on plasmon-assisted chemistry with the long-term aim to establish new materials and new synthesis methods.
The following lists short summaries of the individaul projects in area B.
B01: Surface engineering of plasmonic nanoparticles by the selective cleavage of functional linkers – a pathway towards nanoparticles with functional patches
Alexander Böker, Ilko Bald
This project aims at the generation of functional nanoregions (patches) at nanoparticulate surfaces via the plasmonic cleavage of molecular linkers. During this project, functional linkers will be synthesized, their cleavage process and mechanism will be investigated, the generated patch will be characterised, and the process to prepare functionalized particles in (extended) batches will be optimized.
B02: Two-photon processes and plasmon-induced nitroxide-mediated radical polymerisation (NMP)
Janina Kneipp, Helmut Schlaad
This project aims at characterising and establishing plasmon-induced nitroxide-mediated polymerisation (NMP) that exploits metal nanoparticles as a versatile initiation unit for the fabrication of plasmonic nanoparticle-polymer structures. The excitation of the localized surface plasmon resonance will use conditions that enable efficient two-photon processes for the sensitive vibrational spectroscopic characterisation of the reaction, fast screening of the plasmonic conditions, as well as the extreme localization of high optical fields.
B03: Plasmon-induced RAFT polymerisation as a route to asymmetrically functionalized nanoparticles
Matthias Hartlieb, Ilko Bald
In this project reversible addition-fragmentation chain-transfer (RAFT) polymerisation will be triggered plasmonically by coupling chain transfer agents directly to nanoparticles in order to create asymmetrically functionalized nanoparticles. Different coupling modes will allow for different ways to control the polymerisation, and mechanistic studies will be performed by quartz-crystal microbalance with dissipation (QCM-D) monitoring, surface-enhanced Raman scattering (SERS) and X-ray photoelectron spectroscopy (XPS).
B04: Mechanistic investigation and optimization of plasmon-driven reactions by in-situ analytics and flow chemistry
Heiko Moeller, Claudia Pacholski
This project aims at investigating how the mechanism of plasmon-driven reactions depends on the plasmonic nanomaterials (i.e. their size and morphology) and especially their coverage with ligands by in situ NMR spectroscopy and flow chemistry. A flow reactor setup will be established and 2D and 3D plasmonic nanomaterials will be coated with various ligands to achieve an accurate correlation between the nature and characteristics of the plasmonic material and its activity. This will be done first for two model reactions and later for other reactions studied within the consortium.
B05: Mechanisms of photochemical reactions at metallic nanoparticles
Stefan Hecht, Evgenii Titov
This project aims at uncovering unique features of photochemical transformations in close proximity to metal nanoparticles. Prototypical photoreactions with large thermal activation barriers in the ground state will be studied at and between metal nanoparticles to decipher their underlying mechanisms and to develop a general approach to carry out photochemical transformations at lower excitation energies and with higher efficiencies.