Possible new antiferroelectric compounds for energy storage
ABC compounds are a new class of materials that are believed to exhibit antiferroelectric properties which could be particularly useful for energy storage applications. Most of these materials have never been fabricated, as such there is currently very limited knowledge about their properties and their potential applications. EU-funded scientists from the NAGCESA (Novel antiferroelectric glass-ceramics for energy storage applications) initiative made a start on the synthesis and characterization of the ABC compounds to gain further knowledge on their behaviour. The experimental investigation was mainly carried out on the MgSrSi system, an ABC compound considered to have a model structure for understanding other similar materials. Different synthesis methods for making MgSrSi were used, and the optimum synthesis route based on mechanical alloying was established, with potential use in fabricating other ABC compounds. The research team also investigated the crystal structure, chemical bonds, vibrational properties and electronic bands structure of the MgSrSi compound using ab initio simulations. In addition to the investigation on MgSrSi, NAGCESA studied other potentially antiferroelectric ceramics, including SrSnO3, SrZrO3, CaGeO3 and MgGeO3. It was found that these materials behave as linear dielectrics and are not suitable for energy storage. However, they have shown low dielectric permittivity and loss and they could eventually be suitable for microwave applications. The main contributions of NAGCESA include the identification of a suitable synthesis route for the ABC compounds and an understanding of the effects of processing conditions on the phases and microstructure of the oxide systems studied. The project also resulted in the establishment of a new stream of research on electro-ceramics at a European university.
Keywords
Energy storage, ABC compounds, NAGCESA, MgSrSi, electro-ceramics
