Self-Assembly of Hydrocarbon and Fluorocarbon Surfactants and Their Mixtures at the Mica−Solution Interface

Abstract

The adsorbed layer structure of tetradecylpyridinium, hexadecylpyridinium, heptadecafluorodecylpyridinium, and tetradecyltriethylammonium chloride and their mixtures on mica has been determined by AFM imaging. In addition, the composition of the mixed adsorbed layers has been measured, showing a significant surface enrichment of the pyridinium surfactants, particularly the partially fluorinated species. Shape transitions in the adsorbed layer are correlated with surface and bulk compositions and explained by consideration of the adsorption mechanism.

Self-assembly of acridine orange dye at a mica/solution interface: Formation of nanostripe supramolecular architectures

“…Through aggregation, by changing the slip angle between the constituent molecules or by leaning toward or away from each other, the dyes can optimize their and intermolecular interactions. Hence to construct a surface adsorption model of AO molecules, two acceptable assumptions are made as follows: (i) The dyes have ordered epitaxial attachments to the surface [6][7][8][9][10][11][12][13][14][15][16]. This was confirmed by the fact that we never observed the surface stripe morphology when a glass substrate was used instead of mica.…”

“…Spheres, hemispheres, and cylinders composed of surfactants have been observed at the mica/solution and graphite/solution interfaces. The roles of crystalline substrates, surfactant concentrations, electrolyte, pH value in determining the shape of the interfacial aggregates have been examined, and it is found that the arrangement of surfactants is often analogous to solution structure observed at high surfactant concentrations [6][7][8][9][10][11][12][13][14][15][16]. In these assemblies, the size, shape and spacing of adsorbed aggregates are dependent on the intermolecular (hydrophobic) and surfactant-crystalline substrate interactions [6][7][8][9][10][11][12][13][14][15][16].…”

Adsorption of hexyl--bis(dodecyldimethylammonium bromide) gemini surfactant on silica and its effect on wettability

“…Differently, for the adsorption of the traditional single-chain surfactant, the wormlike micelles or hemimicelles were always found at the solid-solution interfaces by the in situ AFM imaging [10,12,14,19]. This may be attributed to the different molecular nature of the single-chain surfactants and the gemini surfactants.…”

“…It has crucial applications in diverse fields such as detergency, mineral flotation, lubrication, corrosion inhibition, tertiary oil recovery and so on. Over the last few decades, different methods [1][2][3][4][5][6][7][8] have been used to carry out the study of surfactant adsorption at the solid-solution interface [9][10][11][12][13][14][15][16][17] and valuable results have been obtained [18][19][20][21][22][23][24][25][26][27][28][29]. The influence of surfactants on the wettability of solid surfaces has also been studied extensively [30][31][32][33][34][35][36].…”

Sphere to rod transitions in homologous alkylpyridinium salts: A Stauff-Klevens-type equation for the second critical micelle concentration

“…Tetradecylpyridinium chloride (C 14 PyCl) [24] was obtained by treatment of chlorotetradecane with a large excess (9 eq) of pyridine at reflux for 100 h. The reaction mixture was concentrated under vacuum and the residue recrystallized twice from acetone (82% yield) until reaching a purity >99%. The compound was characterized by its spectrometric data and shown by elemental analysis to be a monohydrate.…”