Crosslinking 2D gold nanoparticle assembly at the air-water interface*

We report the results of crosslinking of two-dimensional gold nanoparticle (Au-NP) assemblies at the air-water interface in situ. We introduce an aqueous soluble ruthenium benzylidene catalyst into the water subphase to generate a robust, elastic two-dimensional network of nanoparticles containing cyclic olefins in their ligand framework. The most striking feature of the crosslinked Au-NP assemblies is that the extended connectivity of the nanoparticles enables the film to preserve much of its integrity under compression and expansion, features that are absent in its non-crosslinked counterparts. The crosslinking process appears to “stitch” the nanoparticle crystalline domains together, allowing the crosslinked monolayers to behave like a piece of fabric under lateral compression.