Oxygen contribution on Li-ion intercalation-deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy

Won Sub Yoon, Kwang Bum Kim, Min Gyu Kim, Min Kyu Lee, Hyun Joon Shin, Jay Min Lee, Jae Sung Lee, Chul Hyun Yo

Research output: Contribution to journalArticle

177 Citations (Scopus)

Abstract

To investigate the electronic structure of the electrochemically Li-ion deintercalated Li1-xCoO2 system, soft X-ray absorption spectroscopy (XAS) for the oxygen K-edge and the Co LII,III-edge has been carried out intensively with compositional x value variation, compared with Co K-edge X-ray absorption near edge structure (XANES) spectroscopy. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated Li1-xCoO2 system, we made a binder-free LiCoO2 film electrode using the electrostatic spray deposition (ESD) technique. The oxygen K-edge XAS for Li1-xCoO2 shows more effective spectral change with respect to Li-ion content than the Co LII,III-edge XAS. The dependence of the absorption peak feature on the Li content is described in terms of the ground state of the Co and O atoms, showing the systematic variation of the hole-state site distribution between Co and oxygen atoms. From the Co LII,III-edge XAS, it is found that the broad peak shift to higher energy with the Li-ion deintercalation is due to rehybridization between Co and O atoms under the local structural distortion of CoO6 octahedra, which is also confirmed by the formation of two additional absorption peaks below the threshold energy corresponding to the oxygen 2p hole state hybridized with the 3d orbital of Co ion in the distorted CoO6 octahedral site. In the O K-edge XAS spectra for the deintercalated Li1-xCoO2 film, the shoulder absorption peak in the energy region higher than the threshold energy could be assigned to the higher oxidation state of the oxygen site on Li deintercalation. From the Co LII,III-edge and O K-edge XAS results for the Li-ion deintercalated Li1-xCoO2 film, it is concluded that the charge compensation for the Li-ion deintercalation process could be achieved mainly in the oxygen site and Co metal atomic site simultaneously. OK-edge and Co LII,III-edge XAS results for cycled LiCoO2 film show that the capacity fading of the LiCoO2 system is related to the decrease of Co-O bond covalency by the local structural distortion of CoO6 octahedra remaining in the cycled LiCoO2.

Original languageEnglish
Pages (from-to)2526-2532
Number of pages7
JournalJournal of Physical Chemistry B
Volume106
Issue number10
DOIs
Publication statusPublished - 2002 Mar 14

Fingerprint

X ray absorption spectroscopy
Intercalation
intercalation
absorption spectroscopy
Ions
Oxygen
oxygen
ions
x rays
Atoms
X ray absorption near edge structure spectroscopy
Ground state
Electronic structure
Binders
atoms
Electrostatics
thresholds
energy
Metals
fading

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Cite this

Yoon, Won Sub ; Kim, Kwang Bum ; Kim, Min Gyu ; Lee, Min Kyu ; Shin, Hyun Joon ; Lee, Jay Min ; Lee, Jae Sung ; Yo, Chul Hyun. / Oxygen contribution on Li-ion intercalation-deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy. In: Journal of Physical Chemistry B. 2002 ; Vol. 106, No. 10. pp. 2526-2532.
@article{d26c355429ed42cdafff3a2943385079,
title = "Oxygen contribution on Li-ion intercalation-deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy",
abstract = "To investigate the electronic structure of the electrochemically Li-ion deintercalated Li1-xCoO2 system, soft X-ray absorption spectroscopy (XAS) for the oxygen K-edge and the Co LII,III-edge has been carried out intensively with compositional x value variation, compared with Co K-edge X-ray absorption near edge structure (XANES) spectroscopy. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated Li1-xCoO2 system, we made a binder-free LiCoO2 film electrode using the electrostatic spray deposition (ESD) technique. The oxygen K-edge XAS for Li1-xCoO2 shows more effective spectral change with respect to Li-ion content than the Co LII,III-edge XAS. The dependence of the absorption peak feature on the Li content is described in terms of the ground state of the Co and O atoms, showing the systematic variation of the hole-state site distribution between Co and oxygen atoms. From the Co LII,III-edge XAS, it is found that the broad peak shift to higher energy with the Li-ion deintercalation is due to rehybridization between Co and O atoms under the local structural distortion of CoO6 octahedra, which is also confirmed by the formation of two additional absorption peaks below the threshold energy corresponding to the oxygen 2p hole state hybridized with the 3d orbital of Co ion in the distorted CoO6 octahedral site. In the O K-edge XAS spectra for the deintercalated Li1-xCoO2 film, the shoulder absorption peak in the energy region higher than the threshold energy could be assigned to the higher oxidation state of the oxygen site on Li deintercalation. From the Co LII,III-edge and O K-edge XAS results for the Li-ion deintercalated Li1-xCoO2 film, it is concluded that the charge compensation for the Li-ion deintercalation process could be achieved mainly in the oxygen site and Co metal atomic site simultaneously. OK-edge and Co LII,III-edge XAS results for cycled LiCoO2 film show that the capacity fading of the LiCoO2 system is related to the decrease of Co-O bond covalency by the local structural distortion of CoO6 octahedra remaining in the cycled LiCoO2.",
author = "Yoon, {Won Sub} and Kim, {Kwang Bum} and Kim, {Min Gyu} and Lee, {Min Kyu} and Shin, {Hyun Joon} and Lee, {Jay Min} and Lee, {Jae Sung} and Yo, {Chul Hyun}",
year = "2002",
month = "3",
day = "14",
doi = "10.1021/jp013735e",
language = "English",
volume = "106",
pages = "2526--2532",
journal = "Journal of Physical Chemistry B Materials",
issn = "1520-6106",
publisher = "American Chemical Society",
number = "10",

}

Oxygen contribution on Li-ion intercalation-deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy. / Yoon, Won Sub; Kim, Kwang Bum; Kim, Min Gyu; Lee, Min Kyu; Shin, Hyun Joon; Lee, Jay Min; Lee, Jae Sung; Yo, Chul Hyun.

In: Journal of Physical Chemistry B, Vol. 106, No. 10, 14.03.2002, p. 2526-2532.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Oxygen contribution on Li-ion intercalation-deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy

AU - Yoon, Won Sub

AU - Kim, Kwang Bum

AU - Kim, Min Gyu

AU - Lee, Min Kyu

AU - Shin, Hyun Joon

AU - Lee, Jay Min

AU - Lee, Jae Sung

AU - Yo, Chul Hyun

PY - 2002/3/14

Y1 - 2002/3/14

N2 - To investigate the electronic structure of the electrochemically Li-ion deintercalated Li1-xCoO2 system, soft X-ray absorption spectroscopy (XAS) for the oxygen K-edge and the Co LII,III-edge has been carried out intensively with compositional x value variation, compared with Co K-edge X-ray absorption near edge structure (XANES) spectroscopy. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated Li1-xCoO2 system, we made a binder-free LiCoO2 film electrode using the electrostatic spray deposition (ESD) technique. The oxygen K-edge XAS for Li1-xCoO2 shows more effective spectral change with respect to Li-ion content than the Co LII,III-edge XAS. The dependence of the absorption peak feature on the Li content is described in terms of the ground state of the Co and O atoms, showing the systematic variation of the hole-state site distribution between Co and oxygen atoms. From the Co LII,III-edge XAS, it is found that the broad peak shift to higher energy with the Li-ion deintercalation is due to rehybridization between Co and O atoms under the local structural distortion of CoO6 octahedra, which is also confirmed by the formation of two additional absorption peaks below the threshold energy corresponding to the oxygen 2p hole state hybridized with the 3d orbital of Co ion in the distorted CoO6 octahedral site. In the O K-edge XAS spectra for the deintercalated Li1-xCoO2 film, the shoulder absorption peak in the energy region higher than the threshold energy could be assigned to the higher oxidation state of the oxygen site on Li deintercalation. From the Co LII,III-edge and O K-edge XAS results for the Li-ion deintercalated Li1-xCoO2 film, it is concluded that the charge compensation for the Li-ion deintercalation process could be achieved mainly in the oxygen site and Co metal atomic site simultaneously. OK-edge and Co LII,III-edge XAS results for cycled LiCoO2 film show that the capacity fading of the LiCoO2 system is related to the decrease of Co-O bond covalency by the local structural distortion of CoO6 octahedra remaining in the cycled LiCoO2.

AB - To investigate the electronic structure of the electrochemically Li-ion deintercalated Li1-xCoO2 system, soft X-ray absorption spectroscopy (XAS) for the oxygen K-edge and the Co LII,III-edge has been carried out intensively with compositional x value variation, compared with Co K-edge X-ray absorption near edge structure (XANES) spectroscopy. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated Li1-xCoO2 system, we made a binder-free LiCoO2 film electrode using the electrostatic spray deposition (ESD) technique. The oxygen K-edge XAS for Li1-xCoO2 shows more effective spectral change with respect to Li-ion content than the Co LII,III-edge XAS. The dependence of the absorption peak feature on the Li content is described in terms of the ground state of the Co and O atoms, showing the systematic variation of the hole-state site distribution between Co and oxygen atoms. From the Co LII,III-edge XAS, it is found that the broad peak shift to higher energy with the Li-ion deintercalation is due to rehybridization between Co and O atoms under the local structural distortion of CoO6 octahedra, which is also confirmed by the formation of two additional absorption peaks below the threshold energy corresponding to the oxygen 2p hole state hybridized with the 3d orbital of Co ion in the distorted CoO6 octahedral site. In the O K-edge XAS spectra for the deintercalated Li1-xCoO2 film, the shoulder absorption peak in the energy region higher than the threshold energy could be assigned to the higher oxidation state of the oxygen site on Li deintercalation. From the Co LII,III-edge and O K-edge XAS results for the Li-ion deintercalated Li1-xCoO2 film, it is concluded that the charge compensation for the Li-ion deintercalation process could be achieved mainly in the oxygen site and Co metal atomic site simultaneously. OK-edge and Co LII,III-edge XAS results for cycled LiCoO2 film show that the capacity fading of the LiCoO2 system is related to the decrease of Co-O bond covalency by the local structural distortion of CoO6 octahedra remaining in the cycled LiCoO2.

UR - http://www.scopus.com/inward/record.url?scp=0037076148&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037076148&partnerID=8YFLogxK

U2 - 10.1021/jp013735e

DO - 10.1021/jp013735e

M3 - Article

AN - SCOPUS:0037076148

VL - 106

SP - 2526

EP - 2532

JO - Journal of Physical Chemistry B Materials

JF - Journal of Physical Chemistry B Materials

SN - 1520-6106

IS - 10

ER -