Mechanochemical synthesis and intercalation of Ca(II)Fe(III)-layered double hydroxides

• Synthesis of pristine and amino acid intercalated CaFe-LDHs by two-step milling.
• Identifying the optimum synthesis and intercalation parameters.
• Characterisation of the samples with a range of instrumental methods.

A mechanochemical method (grinding the components without added water – dry grinding, followed by further grinding in the presence of minute amount of water or NaOH solution – wet grinding) was used in this work for the preparation and intercalation of CaFe-layered double hydroxides (LDHs).Both the pristine LDHs and the amino acid anion (cystinate and tyrosinate) intercalated varieties were prepared by the two-step grinding procedure in a mixer mill. By systematically changing the conditions of the preparation method, a set of parameters could be determined, which led to the formation of close to phase-pure LDH. The optimisation procedure was also applied for the intercalation processes of the amino acid anions. The resulting materials were structurally characterised by a range of methods (X-ray diffractometry, scanning electron microscopy, energy dispersive analysis, thermogravimetry, X-ray absorption and infra-red spectroscopies). It was proven that this simple mechanochemical procedure was able to produce complex organic–inorganic nanocomposites: LDHs intercalated with amino acid anions.

Amino acid anion-Ca(II)Fe(III)-LDHs were successfully prepared by a two-step milling procedure.Figure optionsDownload as PowerPoint slide