An effective route to montmorillonite intercalation with imidazole complexes: Experiment and theory

Intercalation of 1H-imidazole (IM) and his derivative 2-phenylimidazole (2-PhIM) into the interlayer spaces of both natural Ca(II)-montmorillonite (Ca-MMT) and Cu(II)-montmorillonite (Cu-MMT) was carried out by two ways, solid-state intercalation and intercalation from solution. Only the presented solid-state intercalation gave required results. In situ formation of Cu complexes in the interlayer spaces of Cu(II)-MMT is not a feasible way to prepare required clay–coordination–intercalation compounds. The Cu complexes of IM and 2-PhIM have been synthesized separately and they were anchored on surface and edges of silicate layers, consequently they were not intercalated into the interlayer spaces of Ca-MMT. X-ray powder diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy were applied to characterize nanocomposites of mentioned above heterocyclic compounds and their Cu complexes with Ca-MMT and/or Cu-MMT. Infrared spectra of intercalation products indicating, that these compounds have been anchored only by non-bonding interactions into interlayer spaces. The experimental data are supported by calculated structure models using molecular dynamics simulations.