Counterion loss from charged surface-bound complexes drives the formation of loosely packed monolayers DOI Creative Commons

Christina Trang,

Carlos Mora Perez, Jingyi Ran

и другие.

Опубликована: Май 29, 2024

The functionality of multicomponent self-assembled monolayers (SAMs) can be severely diminished by the segregation like components into nanoscale domains, a process that maximizes favorable short-range intermolecular interactions. Here, we explore use modular family sulfur-functionalized metal bis(terpyridine) complexes ([M(tpy-R)2]2+(PF6–)2) to prepare mixed SAMs, considering comparable structure, dimensions, and ionic composition these species should render them interchangeable within adsorbed surface layer. While voltammetry experiments show SAMs do exhibit compositions representative their assembly solutions, they also suggest, in line with previous reports, adjacent monolayer are separated gap ~1 nm. Remarkably, X-ray photoelectron spectroscopy studies reveal no F 1s peak features would confirm proliferation PF6− counterions on surface. We propose loose packed structure results from loss or exchange PF6– which introduces significant repulsive Coulomb interactions between 2+ charged complexes. hypothesis is supported an electrostatic model indicates form close if mobile present. First-principles calculations demonstrate complex-counterion binding weakened charge transfer gold substrate, suggesting this may play important role formation such low coverage SAMs. Together, study raises questions regarding assembly, organization, highlights new opportunities design assemblies free volume, for example, facilitate surface-based reactions support molecular switches.

Язык: Английский

Counterion loss from charged surface-bound complexes drives the formation of loosely packed monolayers DOI Creative Commons

Christina Trang,

Carlos Mora Perez, Jingyi Ran

и другие.

Опубликована: Май 29, 2024

The functionality of multicomponent self-assembled monolayers (SAMs) can be severely diminished by the segregation like components into nanoscale domains, a process that maximizes favorable short-range intermolecular interactions. Here, we explore use modular family sulfur-functionalized metal bis(terpyridine) complexes ([M(tpy-R)2]2+(PF6–)2) to prepare mixed SAMs, considering comparable structure, dimensions, and ionic composition these species should render them interchangeable within adsorbed surface layer. While voltammetry experiments show SAMs do exhibit compositions representative their assembly solutions, they also suggest, in line with previous reports, adjacent monolayer are separated gap ~1 nm. Remarkably, X-ray photoelectron spectroscopy studies reveal no F 1s peak features would confirm proliferation PF6− counterions on surface. We propose loose packed structure results from loss or exchange PF6– which introduces significant repulsive Coulomb interactions between 2+ charged complexes. hypothesis is supported an electrostatic model indicates form close if mobile present. First-principles calculations demonstrate complex-counterion binding weakened charge transfer gold substrate, suggesting this may play important role formation such low coverage SAMs. Together, study raises questions regarding assembly, organization, highlights new opportunities design assemblies free volume, for example, facilitate surface-based reactions support molecular switches.

Язык: Английский

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