Mechanochemical synthesis, structure and properties of nanostructured solid fluorides are in the focus of our research interest since many years. In the past few years this comprises mainly the formation of (i) binary fluorides MF2 (M: Mg, Ca, Sr, Ba, Pb), of (ii) solid solutions of fluorides with fluorite-type structure Ma1-xMbxF2 (M: Ca, Sr, Ba, Pb), or (iii) the synthesis of MgF2-MF2 composite systems (M: Ca, Sr, Ba). All solvent-free mechanochemical reactions have in common that they start from different fluorine-free metal sources (acetates, carbonates, hydroxides, alkoxides). The fluorination is initiated directly at milling in a planetary mill using NH4F as fluorinating agent. More spectacular, a simple manual shaking of alkaline earth metal hydroxides with NH4F in the stoichiometric ratio M:F = 1:2 is sufficient to obtain phase pure nanocrystalline MF2 compounds (M: Ca, Sr, Ba). This easy access to binary fluorides makes alkaline earth metal hydroxides to be promising candidates as reactants in the synthesis of inorganic-organic hybrid materials. Both fluorine-free and fluorine-containing coordination polymers of alkaline earth metals are accessible by milling M(OH)2 (M: Ca, Sr, Ba) with non-fluorinated and fluorinated benzene dicarboxylic acids, respectively. Moreover, chemical reactions induced in a planetary mill open an additional possibility to synthesize new coordination polymers not accessible by solution chemistry. The lecture will give an overview about all mentioned fields with examples concerning especially the formation, characterization and properties of solid solutions / composite systems and new coordination polymers.

Mechanochemical synthesis, structure and characterization of fluorine-containing alkaline earth metal compounds

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.