Electrochemically assisted self-assembly of mesoporous silica thin films

Abstract

Supported mesostructured thin films are of major importance for applications in optical, electrochemical and sensing devices. However, good performance is restricted to mesostructured phases ensuring good accessibility from the film surface, which would be straightforward with cylindrical pores oriented normal to the underlying support, but this remains challenging. Here, we demonstrate that electrochemistry is likely to induce self-assembly of surfactant-templated (organo)silica thin films on various conducting supports, homogeneously over wide areas. The method involves the application of a suitable cathodic potential to an electrode immersed in a surfactant-containing hydrolysed sol solution to generate the hydroxyl ions that are necessary to catalyse polycondensation of the precursors and self-assembly of hexagonally packed one-dimensional channels that grow perpendicularly to the electrode surface. The method is compatible with controlled and localized deposition on heterogeneous supports, opening the way to electrochemically driven nanolithography for designing complex patterns of widely accessible mesostructured materials.

Self-assembled templates for the generation of arrays of 1-dimensional nanostructures: From molecules to devices

“…Figure 7(a), displays a cross sectional TEM image of the perpendicular orientation of cylindrical pores after solvent annealing for 48 hour in a chloroform and octane vapour at 20 °C. Another viable approach to vertical arrays involves using electrochemical methods to apply a bias to an electrode in the presence of the silica oligomers and CTAB surfactants, thereby generating hydroxyl ions which promote poly-condensation of the precursors and initiate selfassembly of hexagonally packed one-dimensional channels [87]. Richman and colleagues have used nanoscale epitaxy to promote vertical morphologies in F127 films by carefully selecting a cubic titania structure as the epitaxial under layer [88].…”

Synthesis and characterization of silica nanostructures for cotton leaf worm control

“…Mesoporous metal oxides in nanometer scale have received much attention in the field of research because of their unique physical and chemical properties in terms of large surface areas, hydrothermal stability in organic and inorganic solution phases, and reduced densities [14,15]. Therefore, several of mesoporous metal oxide nanoparticles have been recently synthesized with controlled compositions, structures, and morphologies due to their composition-, structure-, and morphology-dependent properties and applications [16][17][18].…”

Enhancement of the Electrochemical Performance of SWCNT dispersed in a Silica Sol-gel Matrix by Reactive Insertion of a Conducting Polymer

“…An alternative method, which has been the focus of several studies, is the electrochemical or electro-assisted deposition method [5][6][7][8][9]. In particular, Shacham et al.…”