Fine Particle Monolayers Made by a Mobile Dynamic Thin Laminar Flow (DTLF) Device

Abstract

This paper presents an innovative device for monolayer preparation that takes full advantage of the dynamic thin laminar flow method (DTLF). The small cylinder system provided the opportunity to prepare monolayers continuously and transfer them onto a solid substrate while moving. Hydrophilic and hydrophobic surfaces were coated with fine polystyrene particles. Multilayers were also made by simply moving the mobile DTLF device back and forth over the same surface. Technically, this was achieved by controlling the cylinder rotation and translation speeds above the substrate with a set of electrical motors. The injection of various suspensions into the thin liquid film was performed with syringes to make the fluids emerge near the rotating glass surface. The whole assembly was mounted on a mobile platform. Three fine latex particles were selected to make the primary tests of the new DTLF device. In all cases mono- and multilayers were obtained. This device opens a new avenue for the deposition of monolayer strips onto m2 large surfaces.

Fabrication of Large‐Area, Transferable Colloidal Monolayers Utilizing Self‐Assembly at the Air/Water Interface

“…Additionally, careful adjustments of concentration, rotational speed, and surface functionality have to be carried out for each single type of particle. More elaborated equipment has been designed by Picard et al [18] They employed a dynamic thin laminar flow, controlled by a rotating glass rod, to deposit colloidal monolayers on hydrophilic and hydrophobic substrate. Nevertheless, the methods reported so far provide colloidal monolayers of only limited quality in terms of sample area size, defect density, and controllability; in many cases free voids or multilayered regions are formed alongside with the monolayer areas.…”

Fabrication of ordered silicon nanopillars and nanowires by self‐assembly and metal‐assisted etching

“…Monodispersions of nanospheres can be assembled in ordered 2D crystals and arrays on solids or thin films with several methods 16–19, the most common being on a liquid surface by attractive long‐range interactions, in a thin film of liquid spread on a solid using attractive capillary forces or via electrophoretic deposition on the surface of a solid electrode.…”

Evaporation induced self-assembly of ordered structures from a capillary-held solution

“…54 The electrostatic interaction between SiO  groups and the positively charged PDDA enhanced MWNT adhesion to the Si substrate to form a uniform ring. [54][55][56] The synergy of capillary force and electrostatic interaction effectively directed the self-assembly of the MWNTs onto the Si rings over the entire MEH-PPV template. In Method b, where a drop of MWNT/PDDA solution covered only a small part of MEH-PPV ring pattern, the droplet maintained its circular shape and was confined within hydrophobic concentric rings, resulting in a larger, fixed contact angle than in Method a (Figure 6-2b).…”

“…The MWNTs were tethered to Si rings through the electrostatic interaction facilitated by positively charged PDDA (i.e., forming a MWNTs/PDDA/Si layer). [54][55][56] The dimension of the microscopic concentric MWNT rings was significantly affected by the geometric constraints imposed by the MEH-PPV rings. Due to the gradient nature of the template of MEH-PPV rings, gradient concentric MWNT rings were achieved after selective removal of MEH-PPV with toluene, as schematically illustrated in Figure 6-3a.…”

“…4f ) 56,57,58. Recently, most of the colloidal self-assemblies have combined with other techniques or processes to generate precise site-specific adsorption of colloidal particles on the chemically or mechanically tunable surfaces.…”