Insights on the influence of the precursors on the sol-gel synthesis of hybrid organic-inorganic saponite-like materials

Lamellar organic-inorganic hybrid materials, especially talc- and saponite-like structures, have been broadly investigated over the past decades because of the combination of the thermal and mechanical properties of the inorganic part with the possibility to finely tune hydrophilic-hydrophobic balance, ion exchange capacity, and properties through the choice of the silicon source. These compounds are generally produced by coprecipitation or hydrothermal synthesis methods, allowing the formation of well-crystallized particles but it is time and energy consuming. Recently, hybrid organic-inorganic lamellar materials have been synthesized using sol-gel method, which is attractive as it is a one-step method performed under mild conditions, with low energy consumption and short formation times. The originality of this research stands in the study of the influence of the reactants on the formation of saponite-like hybrids and especially on the role of the aluminum source in the sol-gel synthesis of hybrid organic-inorganic lamellar materials. The obtained materials have been characterized by X-ray diffraction, Fourier transform infrared, and solid-state nuclear magnetic resonance spectroscopies and thermogravimetric analysis, and it was shown that hydrotalcite-like compounds can be obtained beside saponite-like compounds depending on the aluminum source. (C) 2019 Published by Elsevier Masson SAS on behalf of Academie des sciences.