Predicting the effect of chain-length mismatch on phase separation in noble metal nanoparticle monolayers with chemically mismatched ligands

Abstract

Enhanced Monte Carlo sampling can be used to predict the morphology of mixed ligand nanoparticle monolayers, providing a step forward in the design of monolayer protected nanoparticles for biosensing, drug delivery, and photonics.

Metallic-Nanoparticle-Based Sensing: Utilization of Mixed-Ligand Monolayers

“…When immiscible (hydrophilic/hydrophobic, hydrogenated/fluorinated) ligands are mixed, ligand arrangement can range from Janus to randomly mixed, depending on the length mismatch and bulkiness differences between the two ligands. 60,63,69,70 Ligand conformation is also affected by the particle size and shape 60,71−73 as well as the ligand exchange method. 17,74 Particle size controls curvature, which affects the distance between neighboring ligands.…”

“…109 The use of theoretical simulations for understanding and designing mixed-ligand monolayers is important for such fundamental understanding. 39 While there have been numerous works focused on understanding and predicting mixed-ligand monolayer conformations through simulations, 53,63,69,79,149 these are very rarely focused on sensing. 150 Fundamental research is further restricted by what may be the largest obstacle currently facing all mixed-ligand particle applications: the difficulty of the monolayer characterization.…”

“…Even so, many studies concerning the interactions between different ligand combinations, and the results of those differences, were conducted and present several general conclusions. When immiscible (hydrophilic/hydrophobic, hydrogenated/fluorinated) ligands are mixed, ligand arrangement can range from Janus to randomly mixed, depending on the length mismatch and bulkiness differences between the two ligands. ,,, Ligand conformation is also affected by the particle size and shape ,− as well as the ligand exchange method. , Particle size controls curvature, which affects the distance between neighboring ligands. Particle shape controls the number of defect sites on the particle surface (such as edges and vertexes), which are the most susceptible to ligand exchange.…”

Quantification of surface composition and segregation on AuAg bimetallic nanoparticles by MALDI MS

“…phase segregation) of binary mixtures of ligand molecules on Au or Ag nanoparticles. [25][26][27][28][29][30][31][32][33] Initially, MALDI, coupled with ion mobility-MS, was used to analyze Au-thiolate complexes desorbed from the nanoparticles. These complexes were interpreted as being composed of surface Au atoms that had desorbed together with the thiolated ligands that were originally attached to them.…”

“…26 The same phenomenon was also reported on Ag nanoparticles. 29,31,34 Our group applied this technique to characterize the evolution of the ligand-shell's morphology during a ligand exchange reaction for Au nanoparticles. 32 We then further improved the characterization of the ligand shell by developing a Monte-Carlo-type simulation capable of reconstructing a model of the ligand shell morphology and provide a distribution of nearest neighbors.…”