Molecular self-assembly

The general objective of our research is to apply molecules as building blocks for the construction of soft materials and nanoscale structures by means of self-assembly. The formation of complex and dynamic superstructures based on small molecules as well as other nanoscale building blocks results in chemical systems featuring new properties that go beyond the simple sum of the single components.

In the field of synthesis and self-assembly, we investigate the self-assembly of molecules and colloids in aqueous solution as well as on surfaces. We employ non-covalent interactions (such as host-guest interactions) to generate larger structures from molecular building blocks. Multiple weak interactions result in a strong and selective multivalent interaction. We have introduced arylazopyrazoles as powerful and versatile molecular photoswitches in a broad range of supramolecular systems. In recent projects we have used host-guest chemistry to guide the assembly of nanoparticles. In the area of surface functionalization by self-assembly, we investigate the preparation and patterning of self-assembled monolayers on solid surfaces. We combine bottom-up self-assembly with top-down lithography, for example to structure surfaces by microcontact printing. Recently we have reported micropatterned SAMs of carbenes on gold surfaces that show enhanced stability and conductivity.

Modular supramolecular system
Modular supramolecular system to assemble dynamic multifunctional nanoparticle aggregates.
© S.Engel

Key references:

  1. A modular system for the design of stimuli-responsive multifunctional nanoparticle aggregates by use of host-guest chemistry
    Engel S, Möller N, Stricker L, Peterlechner M, Ravoo B J. Small  14, 1704287 (2018)
  2. Versatile micropatterns of N-heterocyclic carbenes on gold surfaces: Increased thermal and pattern stability with enhanced conductivity
    Nguyen D T, Freitag M, Ruehling A, Körsgen M, Lamping S, Schaefer A H, Siekman M, Arlinghaus H F, Van der Wiel W G, Glorius F, Ravoo B J.  Angew. Chem. Int. Ed. 57, 11465–11469 (2018)
  3. Arylazopyrazoles as light-responsive molecular switches in cyclodextrin-based supramolecular systems
    Stricker L, Fritz E C, Peterlechner M, Doltsinis N L. Ravoo B J. J. Am. Chem. Soc. 138, 4547–4554 (2016)