Year: 2018
Type: article
Abstract: In crystal growth, surfactants are additive molecules used in dilute amount or as dense, permeable layers to control surface morphologies. We investigate the properties of a strikingly different surfactant: a 2D and covalent layer with close atomic packing, graphene. Using in situ, real-time electron microscopy, scanning tunneling microscopy, kinetic Monte Carlo simulations, and continuum mechanics calculations, we reveal why metallic atomic layers can grow in a 2D manner below an impermeable graphene membrane. Upon metal growth, graphene dynamically opens nanochannels called wrinkles, facilitating mass transport while at the same time storing and releasing elastic energy via lattice distortions. Graphene thus behaves as a mechanically active, deformable surfactant. The wrinkle-driven mass transport of the metallic layer intercalated between graphene and the substrate is observed for two graphene-based systems, characterized by different physicochemical interactions, between graphene and the substrate and between the intercalated material and graphene. The deformable surfactant character of graphene that we unveil should then apply to a broad variety of species, opening new avenues for using graphene as a 2D surfactant forcing the growth of flat films, nanostructures, and unconventional crystalline phases.
Institutions: Institut polytechnique de Grenoble, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Sorbonne Université, Institut Néel, Université Pierre-et-Marie-Curie, Université Grenoble Alpes, ESPCI Paris, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA Grenoble, Institut Nanosciences et Cryogénie, Elettra-Sincrotrone Trieste S.C.p.A.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2798944942