Targeting Ordered Heteroanionic Materials Using Electrosynthesis

点击翻译按钮获取中文摘要

Materials synthesis defines ages. Progression from the bronze age to the iron age only became possible as humans learned how to successfully reduce iron ore into its metallic form. Similarly, modern advances in synthetic technology have lead to the information revolution, and will play a major role in the upcoming quantum era. In order to ensure synthetic science can keep pace with the demands of new technology, it is important to explore new methodologies. Polar materials have unique properties related to their symmetry, including second harmonic generation, piezoelectricity, coupling to dark matter, and unique magnetic properties. Most synthetic schemes to target these materials involve using a polar moiety as a building block, and relying on chance to create a crystal structure with a net polar moment. However, these dipoles will frequently anti-align within a structure, creating a material which is centrosymmetric. By using electrosynthesis, I plan to target non-centrosymmetric materials. Electrosynthesis involves applying an electric bias to a solid state reaction during heating, which will cause heteroanionic materials to be more likely to form polar structures. By adding the extra dimension of voltage to the phase diagram, new materials will be formed in space groups which allow for properties which can only exist in non-centrosymmetric environments. This technique will also be useful for creating ordering in heteroanionic materials. Heteroanionic materials are of great interest in the fields of battery chemistry, photovoltaics and other applications where the optical and electronic properties are of interest. This interest results from the tunability of these systems. However, although anion ordering has been shown to affect these properties it is frequently difficult to control. I plan to use electrosynthesis to induce order/disorder transitions in heteroanionic species, as the anions will have an energetic benefit to aligning parallel to the applied field. By creating a controlled method to induce order in disordered heteroanionic systems, I will be able to conduct a systematic study the relationship between anion placement and optical and electronic properties. In the first 5 years, I plan to develop the methodology for electrosynthesis, proving that this is a viable method for targeting polar materials and determining the limitations of the technique. In the long term, I plan to use this technique to create designer materials to allow the detection of dark matter, and second harmonic generation in the deep UV, and other applications that rely on properties unique to polar materials. Developing new synthetic schemes to make materials which are magnetically interesting will increase the strength of the national research in the field of innovative processes and quantum science. This work will continue to allow Canada to be an international leader in these fields.