Topological synthesis of Mg-based silicate nanosheet bundles from CaSi2 crystal powders

Abstract

Mg-based silicate nanosheet bundles were synthesized by thermal annealing using CaSi2 crystal powders and MgCl2 with the appropriate O2 and/or H2O content in the atmosphere. The silicate compound nanosheet bundle formation was caused by the nanosheet bundle synthesis by Ca-atom extraction from the CaSi2 crystal powders followed by Mg incorporation along with the oxidation and/or hydroxidation by employing the topological synthesis technique. The morphological and structural properties of the Mg2SiO4 nanosheet bundles were clarified and the growth mechanism of the silicate nanosheets was discussed. The growth feature of the Mg-silicates and related materials, such as Mg2Si, MgO, SiO2 and magnesium silicate hydroxides, is discussed from thermodynamic points of view. The possible formation of magnesium silicate hydroxides as a flake-like structure is also mentioned.