Abstract
In many cases, limitations in conventional synthesis routes hamper the accessibility to materials with properties that have been predicted by theory. For instance, metastable compounds with local non-equilibrium structures can hardly be accessed by solid-state preparation techniques often requiring high synthesis temperatures. Also other ways of preparation lead to the thermodynamically stable rather than metastable products. Fortunately, such hurdles can be overcome by mechanochemical synthesis. Mechanical treatment of two or three starting materials in high-energy ball mills enables the synthesis of not only new, metastable compounds but also of nanocrystalline materials with unusual or enhanced properties such as ion transport. In this short review we report about local structures and ion transport of oxides and fluorides mechanochemically prepared by high-energy ball-milling.
Acknowledgments
This short review on mechanosynthesized fluorides and oxides includes selected examples of our studies over the last 6 years (2010–2016) that were funded by the Deutsche Forschungsgemeinschaft (DFG) in the frame of the Priority Programme SPP 1415. We thank our colleagues in Hannover, Karlsruhe and Graz for their help and valuable discussions in achieving the goals of the joint project called “Mechanochemistry of non-equilibrium oxide and fluoride phases: mechanosynthesis, solid state kinetics and spectroscopic properties”. Furthermore, the authors thank Professor K. D. Becker for his continuous and supporting interest in their work. Financial support by the DFG is greatly appreciated.
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