Dr. Vitalii Starchenko
Chemical Sciences Division
Oak Ridge National Laboratory

Growth of Lithium Phosphate Polycrystals in the Flow

ABSTRACT: Comparison between pore-scale models and in-situ experimental observations became an indispensable strategy to study physics and chemistry behind crystal nucleation and growth, shaping materials for applications in nano-, micro-electronics, thermoelectric and energy storage devices. Here a reactive transport pore-scale model is used with explicit moving boundary based on Arbitrary Lagrangian-Eulerian (ALE) approach to understand chemical kinetics and reaction pathways during precipitation of polycrystalline lithium phosphate. This study demonstrates that the shape of precipitate solid particles can be controlled by the reaction pathway and by the ion transport regime rather than by the reaction kinetics. ALE approach allows to capture numerically evolution of solid material interface observed in the in-situ experiment. Most unique advantage of the ALE approach is ability to predict interface dynamics and overall system evolution governed by coupled processes using fundamental values without fitting parameters if they can be calculated ab initio or obtained from prior measurements. By comparing modeling and experiment an earlier proposed hypothesis that the reaction to form solid happens in separate steps is tested.

BIOGRAPHY: Vitalii Starchenko is a research scientist in the Geochemistry and Interfacial Sciences Group in the Chemical Sciences Division at Oak Ridge National Laboratory. Since completing his Ph.D. in Physics of Colloidal Systems in 2009 at the Institute of Biocolloid Chemistry, National Academy of Sciences in Kyiv, Ukraine, he occupied a postdoctoral position in Max Planck Institute for Polymer Research in Mainz, Germany from 2011 to 2013, and a postdoctoral position at the Department of Chemical Engineering, University of Florida in Gainesville, Florida from 2014 to 2016. His research is focused on phase transformations in heterogeneous systems, reaction kinetics and transport at fluid-solid interfaces, and coupling of molecular scale processes and chemistry in porous materials to macroscopic phenomena.