title: Gold Nanoparticle Assemblies on Surfaces: Reactivity Tuning through Capping-Layer and Cross-Linker Design.
abstract: The immobilization of metal nanoparticles (NPs) with molecular control over their organization is challenging. Herein, we report the formation of molecularly cross-linked AuNP assemblies using a layer-by-layer approach. We observed four types of assemblies: 1) small aggregates of individual AuNPs, 2) large aggregates of individual AuNPs, 3) networks of fused AuNPs, and 4) gold islands. Interestingly, these assemblies with the different cross-linkers and capping layers represent different stages in the complete fusion of AuNPs to afford islands of continuous gold. We demonstrate that the stability toward fusion of the nanoparticles of the on-surface structures can be controlled by the reactivity of the cross-linkers and the hydrophilicity/hydrophobicity of the nanoparticles.
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel.
authors.forename: Sreejith
authors.initials: S
authors.lastname: Shankar
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel.
authors.forename: Meital
authors.initials: M
authors.lastname: Orbach
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel.
authors.forename: Revital
authors.initials: R
authors.lastname: Kaminker
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Lahav
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel. milko.vanderboom@weizmann.ac.il.
authors.forename: Milko E
authors.initials: ME
authors.lastname: van der Boom
keywords: aggregation; capping layer; coordination modes; cross-linkers; nanoparticles; surfaces