Triggered reversible phase transformation between layered and spinel structure in manganese-based layered compounds.

ABSTRACT: Irreversible phase transformation of layered structure into spinel structure is considered detrimental for most of the layered structure cathode materials. Here we report that this presumably irreversible phase transformation can be rendered to be reversible in sodium birnessite (Na_xMnO₂·yH₂O) as a basic structural unit. This layered structure contains crystal water, which facilitates the formation of a metastable spinel-like phase and the unusual reversal back to layered structure. The mechanism of this phase reversibility was elucidated by combined soft and hard X-ray absorption spectroscopy with X-ray diffraction, corroborated by first-principle calculations and kinetics investigation. These results show that the reversibility, modulated by the crystal w

SUBMITTER: Jo MR 

PROVIDER: S-EPMC6718664 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature