Related Experiment Video
Updated: Dec 15, 2025
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
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Morphology control in metallosupramolecular assemblies through solvent-induced steric demand
Nils Bäumer1, Kalathil K Kartha, Jasnamol P Palakkal
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany. fernandg@uni-muenster.de.
Soft Matter
|July 8, 2020
Summary
Controlling supramolecular self-assembly is key for functional materials. This study shows solvent polarity dictates aggregate shape, forming nanoparticles in water and nanosheets in non-polar solvents.
Area of Science:
- Supramolecular chemistry
- Materials science
- Nanotechnology
Background:
- Controlling the self-assembly of π-conjugated systems into defined morphologies is crucial for creating functional materials.
- Precise control over aggregation pathways has been achieved through sophisticated protocols and varying experimental conditions.
- The role of solvents with opposing polarities in the self-assembly of building blocks remains an open question.
Purpose of the Study:
- To investigate the effect of aggregation-inducing solvent systems of opposing polarity (aqueous vs. non-polar media) on the supramolecular assembly of a novel bolaamphiphilic Platinum(II) complex.
- To understand how different solvation environments influence the molecular packing and aggregate morphology.
Main Methods:
- Utilized a range of experimental methods to analyze molecular packing and aggregate morphology.
- Employed aqueous and non-polar solvent systems to induce self-assembly.
- Characterized the resulting aggregates using morphological analysis.
Main Results:
- Comparable molecular packing was observed in both aqueous and non-polar media, driven by solvophobic, aromatic, and hydrogen-bonding interactions.
- Aqueous media resulted in restricted aggregate growth, forming spherical nanoparticles.
- Non-polar media led to non-restricted formation of 2D-nanosheets.
Conclusions:
- The different solvation of peripheral solubilizing groups in solvents of opposing polarity is an effective strategy for controlling self-assembly morphology.
- More efficient solvation and increased steric demand of hydrophilic chains in aqueous media, due to water molecule entrapment via hydrogen bonds, restrict aggregate growth.
- This work provides insights into designing self-assembled nanomaterials with controlled morphologies by tuning solvent polarity.
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