Electrochemical approaches for the fabrication and/or characterization of pure and hybrid templated mesoporous oxide thin films: a review

Abstract

Electrochemistry can be used for fabrication and characterization of mesoporous oxide films. First, this review provides insight into the methods used to prepare templated mesoporous thin films on an electrode surface, i.e., evaporation-induced self-assembly (EISA) and electrochemically assisted self-assembly (EASA). Electrochemical characterization of mass transport processes in pure and organically functionalized mesoporous oxide films is then discussed. The electrochemical response can be basically restricted by the electron/mass transfer reaction at the electrode-film interface and diffusion through mesopore channels. The contributions of cyclic voltammetry, hydrodynamic voltammetry, electrochemical impedance spectroscopy, and scanning electrochemical microscopy to the characterization of films with distinct mesostructures are finally described, with special emphasis on identification of conditions that can affect the electrochemical response recorded with such modified electrodes.

Polymer‐Modified Mesoporous Silica Thin Films for Redox‐Mediated Selective Membrane Gating

“…This observation is in agreement with earlier studies performed on comparable mesoporous systems. [ 24,62,63 ] Switching the pH to more acidic environment pH ≤ 3, the silica pore walls are neutralized and electrostatic interactions are "switched off". This is again refl ected in the cyclic voltammograms showing a peak current comparable for both cationic and anionic probe molecules, which is as well comparable to a bare ITO signal, refl ecting unhindered diffusion through the entire mesoporous fi lm until the electrode interface.…”

Immobilization of nanobeads on a surface to control the size, shape, and distribution of pores in electrochemically generated sol–gel films

“…When the goal is to coat an electrode with a sol-gel film, control of the pH at the surface via an electrochemical reaction is a useful method [5]. As initially reported by Mandler and co-workers [6-8], formation of a sol-gel film on a conducting surface can be performed by applying a sufficiently negative potential to a weakly buffered sol to generate hydroxide ion that catalyzes the deposition.…”

Preparation of mesoporous silica templated metal nanostructure on Ni foam substrate and its application for the determination of hydrogen peroxide

“…Separation between anodic and cathodic peaks (DE p ) and values of ferricyanide in curve a is about 60 mV and shows a reversible voltammogram and 96 mV in curve c, after extraction of surfactant. The higher peak-to-peak potential separation and the lower anodic and cathodic peak currents after formation of mesoporous silica on the Ni foam electrode can be related to the electrostatic interactions of this charged specie with negatively charged silanol groups at the channel walls on the electrode surface and indicate the synthesis of negatively charged silanol groups on the electrode surface [27,28].…”

“…7c), the mean value of k was found to be 3.26 9 10 4 cm 3 mol -1 s -1 in the 5.0 mM H 2 O 2 solution. This value for the electron-transfer rate constant is higher than the apparent heterogeneous electron-transfer rate constant reported by GC/SG-Au NP 0.35 9 10 -4 cm 3 mol -1 s -1 [33], 41.9 cm 3 mol -1 s -1 for Hb/PLE [29], 4.9 9 10 3 cm 3 mol -1 s -1 for nanocopper oxide/GC [34] and 5.52 9 10 3 cm 3 mol -1 s -1 for Co 3 O 4 /MWCNT (CPE) [28]. peroxide.…”