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Abstract: Titanosilicate was modified by interlayer surface silylation using octyltriethoxysilane (OTES) and dodecylamine (DDA) in ethanol without a pre-swelling step. The introduction of silyl groups into the interlayer region was confirmed by XRD, FT-IR, RAMAN, SEM, TGA, 29Si NMR and TEM. DDA acts as a gallery expander and silylation catalyst. The evaporation of ethanol from the dispersion yields well-ordered silylation. Layered titanosilicate silicate with large basal spacings between 2.95 and 3.87nm were investigated. The layered structures of the silylated products were confirmed by swelling behavior upon attachment of alkylsilyl groups. Solid-state 29Si MAS NMR of the silylated samples showed Q3 and Q4 signals as well as T2 signals. The increase in the relative intensity of Q4 for Q3 and the appearance of a T2 signal was attributed to the grafting of OTES to the interlayer surface silanol groups. This method provides a promising route for the preparation of new functional nanomaterials to bond a variety of functional groups to the interlayer surface of layered materials. [Copyright &y& Elsevier]

Abstract: Magadiite was modified by interlamellar silylation with octyl triethoxysilane (OTES) in the presence of dodecylamine (DDA) in ethanol without a pre-swelling step. Dodecylamine expanded the interlayer space and acted as silylation catalyst. The well ordered silylated magadiite had basal spacings between 1.18 and 1.38nm. Solid-state 29Si MAS NMR showed Q3 and Q4 signals as well as T2 and T3 signals. The increase in the relative intensity of Q4 for Q3 and the appearance of T2 and T3 signals were attributed to the grafting of OTES to the interlayer surface silanol groups. The described method provides a promising route for the preparation of functional nanomaterials. [Copyright &y& Elsevier]

Abstract: H+-titanosilicate (H4Ti2Si8O22 ·4H2O), formed by proton ion exchange of layered titanosilicate JDF-L1 (Na4Ti2Si8O22 ·4H2O) produced intercalation compounds in DDA (dodecylamine)–TEOS (tetraethylorthosilicate) solution. H+-titanosilicate/DDA/TEOS intercalation compounds rapidly hydrolyzed in pure water to form siloxane-pillared H+-titanosilicates. Calcination of siloxane-pillared H+-titanosilicates for 5h at 500°C in air resulted in the formation of mesoporous silica-pillared H+-titanosilicate (SPT) derivatives. SPT derivatives exhibited refractions corresponding to a basal spacing of 4.16–4.32nm, a uniform pore size of 2.8–3.4nm, and a large surface area of 535–618m2/g. The structures and physical properties of SPT derivatives remained stable after heating for 5h at 700°C in air. These results indicate that DDA molecules have a decisive role in pore formation within SPT derivatives, because they act as a base catalyst and as a template, like surfactant micelles, during the hydrolysis of TEOS. [Copyright &y& Elsevier]

H-kenyaite was modified by interlayer surface silylation using 3-aminopropyltriethoxysilane and dodecylamine in ethanol without a pre-swelling step. Dodecylamine acts as a gallery expander and silylation catalyst. The evaporation of ethanol from the dispersion yields well-ordered silylated kenyaites with large basal spacings between 4.12 and 5.12 nm. Solid-state 29Si MAS NMR of the silylated samples showed Q3 and Q4 signals as well as T2 and T3 signals. The increase in the relative intensity of Q4 for Q3 and the appearance of T2 and T3 signals was attributed to the grafting of 3-aminopropyltriethoxysilane to the interlayer surface silanol groups. [Copyright &y& Elsevier]