Intercalation of [Pt(NH3)4]2+ ions into layered sodium silicate magadiite: a useful method to enhance their stabilisation in a highly dispersed state

Abstract

Al-free layered sodium silicate magadiite has been used as the host material for the stabilisation of [Pt(NH3)4] 2+ ions via intercalation and/or ionexchange reactions. The stabilisation of Pt(NH3)4] 2+ ions in between the layers of Na-magadiite was confirmed by thermogravimetric analysis (TGA), where increased decomposition temperatures were observed for the intercalated materials. The intercalation behaviour of Na-magadiite was evident from the significant uptake of Pt ions (22.2 wt.%). When silica gel was used as the host matrix, negligible uptake of Pt ions (1.3 wt.%) was noticed. The X-ray diffraction (XRD) measurements revealed no appreciable change in the basal spacing of the intercalated materials. Nevertheless, the decrease in the intensity of the 001 peak with increasing Pt loadings (from 13.0 to 22.2 wt.%) substantiated the intercalation of [Pt(NH3)4] 2+ ions within the interlayer spaces of Na-magadiite. The transmission electron microscopy (TEM) studies of the intercalated materials revealed that [Pt(NH3)4] 2+ ions were homogeneously intercalated in the magadiite matrix, ranging from 2-3 nm. Subsequent calcination of the intercalated materials at 600 °C in air led to the formation of Pt nanoparticles supported on silica. The results of XRD and TEM indicated that Pt nanoparticles were highly dispersed on the silica support and were in the range of 5-12 nm. Moreover, chemical analyses confirmed the high loading of Pt on silica in agreement with the TGA results.

Preparation and characterization of Ag-magadiite nanocomposites

“…However, until now, only a limited number of studies have been reported on such nanocomposite materials. 6,9 Recently, we successfully prepared Ag-magadiite nanocomposites based on two types of magadiite materials: Na-magadiite and H-magadiite. For these nanocomposites, it was found that Ag-nanoparticles consisting of a single-crystalline particle with 0955-2219/$ -see front matter © 2006 Elsevier Ltd. All rights reserved.…”

Selective C–C Coupling Reaction of Dimethylphenol to Tetramethyldiphenoquinone Using Molecular Oxygen Catalyzed by Cu Complexes Immobilized in Nanospaces of Structurally-Ordered Materials

“…Magadiite (Na 2 Si 14 O 29 ·nH 2 O) is a layered silicate consisting of negatively charged silicate layers and Na + cations in the interlayer nanospace, and has characteristics such as easy availability by a simple hydrothermal procedure [ 33 ] and high cation-exchange capacity (180 meq/100 g) [ 34 ]. The accessibility and cation-exchange ability of magadiite have led to several applications, for example, adsorbents of metal species [ 35 ] and building units of photofunctional materials [ 36 ].…”

Application of Synthetic Layered Sodium Silicate Magadiite Nanosheets for Environmental Remediation of Methylene Blue Dye in Water

“…SNCM was synthesized using hydrothermal treatment under autogenous pressure at 150 °C of a viscous weak alkaline and SiO 2 -rich area of the ternary system Na 2 O/SiO 2 /H 2 O [ 35 ]. The molar gel composition was 5 SiO 2 :Na 2 O:75 H 2 O.…”