Control of ionic conductivity by lithium distribution in cubic oxide argyrodites Li6+xP1–xSixO5Cl

DOI: 10.1021/jacs.2c09863

Authors: Alexandra Morscher (University of Liverpool) , Benjamin B. Duff (University of Liverpool) , Guopeng Han (University of Liverpool) , Luke M. Daniels (University of Liverpool) , Yun Dang (University of Liverpool) , Marco Zanella (University of Liverpool) , Manel Sonni (University of Liverpool) , Ahmad Malik (University of Liverpool) , Matthew S. Dyer (University of Liverpool) , Ruiyong Chen (University of Liverpool) , Frédéric Blanc (University of Liverpool) , John B. Claridge (University of Liverpool) , Matthew J. Rosseinsky (University of Liverpool)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of The American Chemical Society , VOL 360

State: Published (Approved)
Published: November 2022
Diamond Proposal Number(s): 23666 , 21726

Abstract: Argyrodite is a key structure type for ion-transporting materials. Oxide argyrodites are largely unexplored despite sulfide argyrodites being a leading family of solid-state lithium-ion conductors, in which the control of lithium distribution over a wide range of available sites strongly influences the conductivity. We present a new cubic Li-rich (>6 Li+ per formula unit) oxide argyrodite Li7SiO5Cl that crystallizes with an ordered cubic (P213) structure at room temperature, undergoing a transition at 473 K to a Li+ site disordered F4̅3m structure, consistent with the symmetry adopted by superionic sulfide argyrodites. Four different Li+ sites are occupied in Li7SiO5Cl (T5, T5a, T3, and T4), the combination of which is previously unreported for Li-containing argyrodites. The disordered F4̅3m structure is stabilized to room temperature via substitution of Si4+ with P5+ in Li6+xP1–xSixO5Cl (0.3 < x < 0.85) solid solution. The resulting delocalization of Li+ sites leads to a maximum ionic conductivity of 1.82(1) × 10–6 S cm–1 at x = 0.75, which is 3 orders of magnitude higher than the conductivities reported previously for oxide argyrodites. The variation of ionic conductivity with composition in Li6+xP1–xSixO5Cl is directly connected to structural changes occurring within the Li+ sublattice. These materials present superior atmospheric stability over analogous sulfide argyrodites and are stable against Li metal. The ability to control the ionic conductivity through structure and composition emphasizes the advances that can be made with further research in the open field of oxide argyrodites.

Diamond Keywords: Batteries; Solid-State Batteries (SSB)

Subject Areas: Chemistry, Materials, Energy


Instruments: I11-High Resolution Powder Diffraction , I19-Small Molecule Single Crystal Diffraction

Added On: 24/11/2022 08:59

Documents:
1-s2.0-S1570963922001145-main.pdf

Discipline Tags:

Energy Storage Energy Physical Chemistry Energy Materials Chemistry Materials Science

Technical Tags:

Diffraction Single Crystal X-ray Diffraction (SXRD) X-ray Powder Diffraction