Nanocomposites and nanomaterials

A novel method of ordering nanoparticles in photosensitive organic nanotubes
Jedrych A.1, Pawlak M.1, Lewandowski W. 1, Wojcik M.1
1 Faculty of Chemistry, University of Warsaw, Pasteura 1 Street, 02-093 Warsaw, Poland
E-mail: ajedrych@chem.uw.edu.pl

Directed self-assembly can be guided by tailoring the intrinsic characteristics of nanoparticles or by the presence of external fields [1]. Unfortunately, the high level of nanoparticle ordering is often insufficient to create a material with interesting properties. Among rich repertoire of external inputs that can influence the state of a material, light seems to be extremely interesting [2]. 
In our work, we develop a novel strategy of self-assembling of plasmonic gold nanoparticles covered with mesogenic ligands in photosensitive organic liquid-crystalline template in thin films. Nanoparticles are self-assembling inside the organic nanotubes, which are made of layers of bent-shaped dimers with azobenzene groups (Fig.1). Our approach can be successfully used for organizing nanoparticles with various size and shape. It must be stressed that the most important advantage of obtained material is its dual-responsivity. The structure can be controlled by a change in temperature as well as by UV-light irradiation.

Figure 1. TEM image of self-assembled nanoparticles in organic nanotubes.
The research is conducted under project carried out within the Opus programme of National Science Centre (GR 6376).

1.	Grzelczak M., Varmant J., Furst M., Liz Marzan L.M. Directed Self-Assembly of Nanoparticles // ACS Nano.-2010.-4.-P. 3591-3605
2.	Klajn R. Spiropyran-based dynamic materials Chemical Society Reviews.-2014.-43, -P. 148-184.