Transition metal migration can facilitate ionic diffusion in defect garnet based intercalation electrodes

DOI: 10.1021/acsenergylett.0c00376

Authors: Nicholas H Bashian (University of Southern California) , Samantha Abdel-Latif (University of Southern California) , Mateusz Zuba (Binghamton University) , Kent J. Griffith (University of Cambridge) , Alex M. Ganose (University College London) , Joseph W. Stiles (University of Southern California) , Shiliang Zhou (University of Southern California) , David O. Scanlon (University College London; Diamond Light Source; The Faraday Institution) , Louis F. J. Piper (Binghamton University) , Brent Melot (University of Southern California)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acs Energy Letters

State: Published (Approved)
Published: April 2020

Abstract: The importance of metal migration during multi-electron redox activity has been characterized, revealing a competing demand to satisfy bonding requirements and local strains in structures upon alkali intercalation. The local structural evolution required to accommodate intercalation in Y2(MoO4)3 and Al2(MoO4)3 has been contrasted by operando characterization methods, including X-ray absorption spectroscopy and diffraction, along with nuclear magnetic resonance measurements. Computational modeling further rationalized behavioral differences. The local structure of Y2(MoO4)3 was maintained upon lithiation while the structure of Al2(MoO4)3 underwent substantial local atomic rearrangements as the stronger ionic character of the bonds in Al2(MoO4)3 allowed Al to mix off its starting octahedral position to accommodate strain during cycling. However, this mixing was prevented in the more covalent Y2(MoO4)3 which accommodated strain through rotational motion of polyhedral subunits. Knowing that an increased ionic character can facilitate the diffusion of redox-inactive metals when cycling multi-electron electrodes offers a powerful design principle when identifying next-generation intercalation hosts.

Diamond Keywords: Batteries; Lithium-ion

Subject Areas: Chemistry, Energy, Materials

Facility: Advanced Photon Source

Added On: 06/04/2020 10:16

Discipline Tags:

Energy Storage Energy Physical Chemistry Energy Materials Chemistry Materials Science

Technical Tags: