Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 9 (1), 947

Elucidating Anionic Oxygen Activity in Lithium-Rich Layered Oxides

Affiliations

Elucidating Anionic Oxygen Activity in Lithium-Rich Layered Oxides

Jing Xu et al. Nat Commun.

Abstract

Recent research has explored combining conventional transition-metal redox with anionic lattice oxygen redox as a new and exciting direction to search for high-capacity lithium-ion cathodes. Here, we probe the poorly understood electrochemical activity of anionic oxygen from a material perspective by elucidating the effect of the transition metal on oxygen redox activity. We study two lithium-rich layered oxides, specifically lithium nickel metal oxides where metal is either manganese or ruthenium, which possess a similar structure and discharge characteristics, but exhibit distinctly different charge profiles. By combining X-ray spectroscopy with operando differential electrochemical mass spectrometry, we reveal completely different oxygen redox activity in each material, likely resulting from the different interaction between the lattice oxygen and transition metals. This work provides additional insights into the complex mechanism of oxygen redox and development of advanced high-capacity lithium-ion cathodes.

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Structural characterization of pristine Li1.2Ni0.2Mn0.6O2 (LNMO) and Li1.2Ni0.2Ru0.6O2 (LNRO). a Synchrotron XRD patterns, showing a similar crystal structure between these two compounds; XRD Rietveld refinement of b LNMO based on monoclinic C2/m and c LNRO based on monoclinic C2/c; d scanning electron microscopy (SEM) image of LNMO, the scale bar is 1 μm; e, f high-resolution transmission electron microscopy (HRTEM) images of LNMO with fast Fourier transform (FTT) of the selected area, the scale bar in (e) and (f) is 50 and 5 nm, respectively; g electron diffraction (ED) pattern for LNMO; h SEM image of LNRO, the scale bar is 1 μm; i, j HRTEM images of LNRO with FTT of the selected area, the scale bar in (i) and (j) is 100 and 2 nm, respectively; k ED pattern for LNRO
Fig. 2
Fig. 2
First charge–discharge characteristics of LNMO and LNRO. The first cycle voltage profile of a LNMO and b LNRO; differential capacity (dQ/dV) plot of c LNMO and d LNRO. Cells were cycled between 4.8 and 2.0 V at a current density of 5 mA g–1 at room temperature
Fig. 3
Fig. 3
Gas evolution of LNMO and LNRO by operando DEMS. The first cycle voltage profiles and gas evolution rates of a LNMO and b LNRO. The total active cathode material used for the measurement was 32.9 mg LNMO (387 μmol) and 28.6 mg LNRO (253 μmol). Cells were cycled between 4.8 and 2.0 V, at a current of 10 mA g–1
Fig. 4
Fig. 4
Electronic structures of Ni and O as probed by sXAS. sXAS Ni L3-edge spectra of a LNMO and b LNRO electrodes; sXAS O K-edge spectra of c LNMO and d LNRO electrodes in FY and TEY modes at different states of charge. Solid and dash line indicate FY and TEY mode, respectively
Fig. 5
Fig. 5
Electronic structures of O as probed by RIXS. O K-edge RIXS maps of a LNMO and b LNRO electrodes at different states of charge. The while arrow points to the specific oxygen redox state that is absent in LNRO
Fig. 6
Fig. 6
Electronic structure of Ru as probed by in situ XAS. In situ a, b XANES, c voltage profile, d, e EXAFS of Ru K-edge of LNRO during the first cycle. The in situ cell was charged at C/10 and discharged at C/7

Similar articles

See all similar articles

Cited by 3 PubMed Central articles

References

    1. Whittingham MS. Lithium batteries and cathode materials. Chem. Rev. 2004;104:4271–4301. doi: 10.1021/cr020731c. - DOI - PubMed
    1. Goodenough JB, Kim Y. Challenges for rechargeable Li batteries. Chem. Mater. 2010;22:587–603. doi: 10.1021/cm901452z. - DOI
    1. Etacheri V, Marom R, Elazari R, Salitra G, Aurbach D. Challenges in the development of advanced Li-ion batteries: a review. Energ. Environ. Sci. 2011;4:3243–3262.
    1. Andre D, et al. Future generations of cathode materials: an automotive industry perspective. J. Mater. Chem. A. 2015;3:6709–6732. doi: 10.1039/C5TA00361J. - DOI
    1. Liu W, et al. Nickel-rich layered lithium transition-metal oxide for high-energy lithium-ion batteries. Angew. Chem. Int. Ed. 2015;54:4440–4457. doi: 10.1002/anie.201409262. - DOI - PubMed

Publication types

Feedback