Silica-layered double hydroxide nanoarchitectured materials

Abstract

This work shows the viability for assembling layered double hydroxides (LDH) containing surfactant anions in its interlayer region, with silicon alkoxides through a sol-gel processes, leading to SiO2-LDH nanoarchitectured materials consisting in delaminated LDH particles assembled to silica nanoparticles. Tetrametoxysilane (TMOS) has been used as silica precursor being hydrolyzed and polycondensed in presence of MgAl-, NiAl- and NiCoFe-LDH containing dodecylsulphate ions as interlayer anions. The resulting materials were further heated to remove the organic matter and to consolidate the final nanoarchitecture, being the LDH re-constructed in a final step in the presence of a salt solution (e.g., Na2CO3, sodium dodecysulphate, …), producing LDH-SiO2 materials. These resulting materials have being characterized using XRD, FTIR, 29Si and 27Al NMR spectroscopy, N2 adsorption-desorption isotherms, FE-SEM and TEM amongst other physical-chemical characterization techniques. The obtained results confirm the formation of silica nanoparticles within the nanosheets generated by delamination of the pristine LDH, producing functional materials of elevated specific surface area of potential interest in diverse fields of applications.