"Precipitation on Nanoparticles": Attractive Intermolecular Interactions Stabilize Specific Ligand Ratios on the Surfaces of Nanoparticles. Issue 24 (15th May 2018)

• Record Type: Journal Article
• Authors: Chu, Zonglin; Han, Yanxiao; Král, Petr; Klajn, Rafal
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 24(2018)
• Page Start: 7023
• Page End: 7027
• Publication Date: 2018-05-15
• Subjects: ligand exchange -- nanoparticles -- self-assembly -- supramolecular chemistry -- surface chemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201800673
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Confining organic molecules to the surfaces of inorganic nanoparticles can induce intermolecular interactions between them, which can affect the composition of the mixed self‐assembled monolayers obtained by co‐adsorption from solution of two different molecules. Two thiolated ligands (a dialkylviologen and a zwitterionic sulfobetaine) that can interact with each other electrostatically were coadsorbed onto gold nanoparticles. The nanoparticles favor a narrow range of ratios of these two molecules that is largely independent of the molar ratio in solution. Changing the solution molar ratio of the two ligands by a factor of 5 000 affects the on‐nanoparticle ratio of these ligands by only threefold. This behavior is reminiscent of the formation of insoluble inorganic salts (such as AgCl), which similarly compensate positive and negative charges upon crystallizing. Our results pave the way towards developing well‐defined hybrid organic–inorganic nanostructures. Abstract : A marriage made on a nanoparticle : Co‐adsorption of two different ligands on the same nanoparticle is shown to stabilize over a narrow range of ratios of these molecules. The effect is attributed to electrostatic interactions induced by adsorption on the nanoparticles and is corroborated by molecular dynamics simulations.