Understanding crystallization pathways leading to manganese oxide polymorph formation. Journal Article uri icon

Overview

abstract

  • Hydrothermal synthesis is challenging in metal oxide systems with diverse polymorphism, as reaction products are often sensitive to subtle variations in synthesis parameters. This sensitivity is rooted in the non-equilibrium nature of low-temperature crystallization, where competition between different metastable phases can lead to complex multistage crystallization pathways. Here, we propose an ab initio framework to predict how particle size and solution composition influence polymorph stability during nucleation and growth. We validate this framework using in situ X-ray scattering, by monitoring how the hydrothermal synthesis of MnO2 proceeds through different crystallization pathways under varying solution potassium ion concentrations ([K+] = 0, 0.2, and 0.33 M). We find that our computed size-dependent phase diagrams qualitatively capture which metastable polymorphs appear, the order of their appearance, and their relative lifetimes. Our combined computational and experimental approach offers a rational and systematic paradigm for the aqueous synthesis of target metal oxides.

publication date

  • June 29, 2018

Full Author List

  • Chen B-R; Sun W; Kitchaev DA; Mangum JS; Thampy V; Garten LM; Ginley DS; Gorman BP; Stone KH; Ceder G

Other Profiles

Additional Document Info

start page

  • 2553

volume

  • 9

issue

  • 1