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N. Hayati-Roodbari, R. Berger, J. Bernardi, S. Kinge, N. Hüsing, M. Elsässer:
"From sol-gel prepared porous silica to monolithic porous Mg2Si/ MgO composite materials";
Journal of Sol-Gel Science and Technology, 88 (2018), 1 - 8.

Mg2Si is apart from its conductivity properties expected to be a promising candidate for thermoelectric applications due to its
low toxicity, low costs, and the high abundance of its precursor chemicals. Through the addition of a homogeneous
distribution of nanoparticles (e.g. MgO) and by reducing the size of Mg2Si to the nanometer regime, it is possible to decrease
the thermal conductivity by increasing phonon-interface scattering and, as a result, improve the thermoelectric properties.
However, classical approaches do not allow for the synthesis of nanocomposites from Mg2Si and MgO. In this work, a
straightforward route is presented towards homogeneously mixed Mg2Si/MgO via a two-step magnesiothermic reduction
process starting from sol-gel derived hierarchically organized porous silica. Monolithic materials composed of Mg2Si and
MgO in variable molar ratios are built up from a macroporous network of Mg2Si with homogeneously distributed MgO
particles exhibiting a crystallite size in the range of 24-37 nm.

http://dx.doi.org/10.1007/s10971-018-4778-8