01/16/20 - 9:45 AM to 11:00 AM
Department Seminar: Andrew Martinolich, Ph.D.
Controlling Solid State Reactivity, Diffusion, and Redox: Reaction and Materials Discovery for Next-Generation Energy Storage
Greater control over solid state reactivity and diffusion will enable the design and discovery of new functional inorganic materials. Traditional solid state chemistry depends on the application of high temperatures and long reaction times to overcome solid state diffusion, which in turn yields the most thermodynamically stable product. In order to promote the formation of kinetically stable materials, alternative reaction pathways are required. Here, we describe the use of solid state metathesis reactions to couple the formation of transition metal chalcogenides with the formation of salt as a byproduct, which enables reactivity at low temperature and kinetic control over the products. Further alteration of the reaction pathway to overcome solid state diffusion allows for pathway- and polymorph-selective control, shifting towards a paradigm of solid state reaction-by-design. Designing solid state electrolytes and cathodes tailored for next generation battery technologies presents an alternative challenge, in that the rules governing the chemistry-structure-property relationships for such applications have yet to be rigorously determined. Here, we will present the discovery of Zn2+ conductivity in the electronically insulating material ZnPS3, which is enabled by the polyatomic anion flexibility and layered nature of the 2D. Towards the development of multielectron redox chemistry in Li ion based batteries, the discovery of the cathode material Li2FeSe2 and its tunable anion redox through the formation of an anionic solid solution will also be discussed.
Andrew "Andy" Martinolich is a Resnick Postdoctoral Fellow, working to design inorganic materials to function as solid state electrolytes for next-general batteries at the California Institute of Technology. He earned his bachelor's degree in chemistry from Santa Clara University, investigating the interactions between silver nanoparticles and the metalloprotein azurin in order to study the possible effects of nanotechnology on human health. His graduate studies at Colorado State University primarily focused on the development of kinetic control in solid state chemical reactions in order to design reactions that would yield metastable inorganic materials with favorable electronic and physical properties.