Formation of Thin Films of Clay−Organic Complexes with an Application as an Electrode Modifier

Abstract

A thin film was formed by spreading a chloroform dispersion of a hydrophobic clay-organic complex at an air-water interface. The clay-organic complexes were prepared by reacting synthetic saponite with 3-(aminopropyl)dimethylethoxysilane and thereafter with alkanoyl chlorides. From the analysis of surface pressure-area curves, it was concluded that the film were composed of 1-3 layers of clay crystallites. The film was repeatedly transferred onto a glassy carbon electrode to build up 30 layers by the Langmuir-Blodgett method. An electrode modified with the clay multilayer was found to be electroactive when it was soaked in an aqueous solution of [Ru(bpy) 3]Cl2 (1 × 10 -5 M) and Na2SO4 (0.05 M).

Hydrophobic Modification of Layered Clays and Compatibility for Epoxy Nanocomposites

“…The intercalation or organic incorporation is accompanied with a silicate gallery expansion. For example, the C 18 -alkyl quaternary salts could expand MMT interlayer spacing to 20−30 Å basal spacing from 12 Å in the original clay [ 25 , 26 , 27 , 28 ]. It was noticed that the same organic salt could not exchange with the clays with divalent counter ions such as Mg 2+ or Ca 2+ in MMT [ 29 ].…”

Synthesis of novel hybrid films of a layered silicate and alkylammonium cations on rough polymeric surfaces by Langmuir–Blodgett method

“…The LangmuirBlodgett (LB) method has been widely utilized to form a hybrid monofilm of clay minerals and amphiphilic molecules since the pioneering works of Kotov et al and Inukai et al in 1994 [7-16]. The advantages of this method are: (a) the film is fabricated by layer-by-layer and both the individual clay layer and the amphiphilic molecules have highly ordered arrangement; (b) the film can be transferred to either hydrophilic or hydrophobic substrates; (c) the film may carry different functions such as electroactivity [17], chiral sensor [18] and magnetism [19] due to the nature of the amphiphilic molecules and the organization of both the amphiphilic molecules and the elementary clay layers [20].…”

“…The organization of the clay particles and amphiphilic molecules of the hybrid film have been studied [27][28][29]. Others characterized the functionality of such films [17,30]. The clay layers have been observed to be highly oriented parallel to the substrate surface and form a layered structure in the hybrid films [9,27].…”

Surface modification of polymeric nanocomposite thin films using supercritical carbon dioxide

“…In addition, gold nanoparticles added to polymers are known to significantly enhance various physical properties such as UV absorption, electrical conductivity and optical dispersion [13][14][15]. In order to probe the effect of aspect, we also studied thin films with functionalized clay particles, which are often added to polymers in order to increase thermal and UV stability, as well as enhancement of mechanical properties [16,17]. We used X-ray reflectivity (XR) to study film structures with the nanoparticles on the molecular scale.…”