Gold Nanoparticle Networks with Photoresponsive Interparticle Spacings

Abstract

Photoresponsive gold nanoparticle networks were prepared by functionalizing them with azobenzene derivatives. A network can be formed when a linker molecule constituting the azobenzene moiety suitably derivatized on either side with gold surface sensitive groups such as thiols and amines is added to the nanoparticle solution. It is shown that the interparticle spacing in the networks could be controlled by the reversible trans-cis isomerization of the azobenzene moiety induced by UV and visible light, respectively. The photoinduced variation in the interparticle spacings is inferred by the changes in the optical spectra of the gold nanoparticles which display a red or blue shift in the surface plasmon resonance peak depending on a decrease or increase in the interparticle spacing, respectively. Transmission electron microscopy images are in consonance with the evidence from the optical spectra.

Functionalized gold nanoparticles: Synthesis, structure and colloid stability

“…Chromophores such as azobenzene or spiropyrene have been attached to oxides or metal particle surfaces as terminal groups [49,52,98,[127][128][129][130][131][132]. Spiropyrene has closed and opened structures, which are switchable upon light irradiation.…”

Gold nanoparticle superlattices

“…27 In any case, the resulting aggregates are always spherical and obtaining a 3-D ordered crystalline array seems to be difficult with this procedure. 29 As the azobenzene undergoes light induced cis-trans conformational changes the nanoparticle networks linked by these molecules become denser (Fig. 8) to this process by modifying the nanoparticle surface with mercaptoaniline and linking the exposed amine groups with succinyl chloride.…”

Preparation and Characterization of Gold Nanoparticles with Different Capping Agents

“…[1][2][3][4] Metal nanoparticles exhibit appreciable physical, chemical, and optical properties from those of the bulk materials. [5] Nanoparticles by themselves and when used as building blocks to construct complex nanostructured materials and devices.…”