Photochromic nanostructures based on diarylethenes with perylene diimide
Lulu Ma1, Quanbo Wang, Guifen Lu
1Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, PR China.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 29, 2009
Summary
Researchers developed a photochromic dyad (BTE-PDI) that self-assembles into nanotubes. These nanostructures exhibit a hierarchical assembly process and photochromic switching behavior, demonstrating potential for advanced materials.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Nanotechnology
Background:
- Perylene diimides (PDIs) are known for their excellent photophysical properties.
- Photochromic materials offer tunable optical properties upon light irradiation.
- Self-assembly is a key strategy for creating ordered nanostructures.
Purpose of the Study:
- To synthesize a bisthienylethene-functionalized perylene diimide (BTE-PDI) photochromic dyad.
- To investigate the self-assembly behavior of BTE-PDI into one-dimensional (1-D) nanotubes.
- To explore the photochromic properties and hierarchical assembly of the resulting nanostructures.
Main Methods:
- Reprecipitation method for self-assembly.
- Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) for morphological analysis.
- Infrared (IR) spectroscopy, X-ray Diffraction (XRD), and UV-Vis absorption and fluorescence spectroscopy for structural and electronic characterization.
Main Results:
- Hierarchical self-assembly of BTE-PDI from hollow nanospheres to 1-D nanotubes was observed.
- Highly ordered lamellar structures were found in both nanospheres and nanotubes.
- Intermolecular hydrogen bonds and various non-covalent interactions (dipole-dipole, pi-pi stacking, hydrophilic/hydrophobic) drive the assembly.
- H-aggregate nature of the self-assembled nanostructures was confirmed.
- Photochromic switching behavior was demonstrated with green emission tunable by 365 nm light.
Conclusions:
- BTE-PDI molecules self-assemble into hierarchical nanostructures with ordered lamellar arrangements.
- The nanostructures exhibit photochromic properties, functioning as light-responsive switches.
- The study highlights the potential of BTE-PDI for applications in photochromic materials and nanotechnology.
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