Neutron and X-ray diffraction study of pyrophosphate-based Li 2-xMP2O7 (M = Fe, Co) for lithium rechargeable battery electrodes

Hyungsub Kim; Seongsu Lee; Young Uk Park; Haegyeom Kim; Jongsoon Kim; Seokwoo Jeon; Kisuk Kang

doi:10.1021/cm201305z

Neutron and X-ray diffraction study of pyrophosphate-based Li _2-xMP₂O₇ (M = Fe, Co) for lithium rechargeable battery electrodes

Hyungsub Kim, Seongsu Lee, Young Uk Park, Haegyeom Kim, Jongsoon Kim, Seokwoo Jeon, Kisuk Kang

Research output: Contribution to journal › Article › peer-review

110 Scopus citations

Abstract

Structural characterization of Li_2-xMP₂O₇ (M = Fe, Co) was carried out using neutron diffraction (ND) and X-ray diffraction (XRD) analyses to elucidate structural information and structural changes during an electrochemical reaction. The crystal system and space group were determined to be monoclinic P2₁/c for both materials with a = 11.0192 (4) Å, b = 9.7488 (3) Å, c = 9.8057 (4) Å, and β = 101.569 (3)° for Li_2-xFeP₂O₇ and a = 10.9574 (3), b = 9.6921 (3), c = 9.7611 (3), and β = 101.776 (2)° for Li_2-xCoP₂O₇. XRD analysis revealed partial occupancy of iron and cobalt in the structures of Li_2-xFeP ₂O₇ and Li_2-xCoP₂O₇, respectively. Also, ND identified lithium positions and partial occupancies in five different Li sites of Li_2-xMP₂O₇ (M = Fe, Co). Further ex situ XRD showed that the charging/discharging of Li _2-xFeP₂O₇ occurred primarily via a two-phase reaction with a slight solid solution behavior. We also demonstrated for the first time that Li_2-xCoP₂O₇ electrodes are electrochemically active, with a redox potential of ∼5 V (versus Li).

Original language	English
Pages (from-to)	3930-3937
Number of pages	8
Journal	Chemistry of Materials
Volume	23
Issue number	17
DOIs	https://doi.org/10.1021/cm201305z
State	Published - 13 Sep 2011
Externally published	Yes

Keywords

Li MPO (M = Fe Co)
neutron diffraction
Structural characterization
X-ray diffraction

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1021/cm201305z

Cite this

@article{407ba00fc5ad494687e3832cbf728b81,

title = "Neutron and X-ray diffraction study of pyrophosphate-based Li 2-xMP2O7 (M = Fe, Co) for lithium rechargeable battery electrodes",

abstract = "Structural characterization of Li2-xMP2O7 (M = Fe, Co) was carried out using neutron diffraction (ND) and X-ray diffraction (XRD) analyses to elucidate structural information and structural changes during an electrochemical reaction. The crystal system and space group were determined to be monoclinic P21/c for both materials with a = 11.0192 (4) {\AA}, b = 9.7488 (3) {\AA}, c = 9.8057 (4) {\AA}, and β = 101.569 (3)° for Li2-xFeP2O7 and a = 10.9574 (3), b = 9.6921 (3), c = 9.7611 (3), and β = 101.776 (2)° for Li2-xCoP2O7. XRD analysis revealed partial occupancy of iron and cobalt in the structures of Li2-xFeP 2O7 and Li2-xCoP2O7, respectively. Also, ND identified lithium positions and partial occupancies in five different Li sites of Li2-xMP2O7 (M = Fe, Co). Further ex situ XRD showed that the charging/discharging of Li 2-xFeP2O7 occurred primarily via a two-phase reaction with a slight solid solution behavior. We also demonstrated for the first time that Li2-xCoP2O7 electrodes are electrochemically active, with a redox potential of ∼5 V (versus Li).",

keywords = "Li MPO (M = Fe Co), neutron diffraction, Structural characterization, X-ray diffraction",

author = "Hyungsub Kim and Seongsu Lee and Park, \{Young Uk\} and Haegyeom Kim and Jongsoon Kim and Seokwoo Jeon and Kisuk Kang",

year = "2011",

month = sep,

day = "13",

doi = "10.1021/cm201305z",

language = "English",

volume = "23",

pages = "3930--3937",

journal = "Chemistry of Materials",

issn = "0897-4756",

publisher = "American Chemical Society",

number = "17",

}

TY - JOUR

T1 - Neutron and X-ray diffraction study of pyrophosphate-based Li 2-xMP2O7 (M = Fe, Co) for lithium rechargeable battery electrodes

AU - Kim, Hyungsub

AU - Lee, Seongsu

AU - Park, Young Uk

AU - Kim, Haegyeom

AU - Kim, Jongsoon

AU - Jeon, Seokwoo

AU - Kang, Kisuk

PY - 2011/9/13

Y1 - 2011/9/13

N2 - Structural characterization of Li2-xMP2O7 (M = Fe, Co) was carried out using neutron diffraction (ND) and X-ray diffraction (XRD) analyses to elucidate structural information and structural changes during an electrochemical reaction. The crystal system and space group were determined to be monoclinic P21/c for both materials with a = 11.0192 (4) Å, b = 9.7488 (3) Å, c = 9.8057 (4) Å, and β = 101.569 (3)° for Li2-xFeP2O7 and a = 10.9574 (3), b = 9.6921 (3), c = 9.7611 (3), and β = 101.776 (2)° for Li2-xCoP2O7. XRD analysis revealed partial occupancy of iron and cobalt in the structures of Li2-xFeP 2O7 and Li2-xCoP2O7, respectively. Also, ND identified lithium positions and partial occupancies in five different Li sites of Li2-xMP2O7 (M = Fe, Co). Further ex situ XRD showed that the charging/discharging of Li 2-xFeP2O7 occurred primarily via a two-phase reaction with a slight solid solution behavior. We also demonstrated for the first time that Li2-xCoP2O7 electrodes are electrochemically active, with a redox potential of ∼5 V (versus Li).

AB - Structural characterization of Li2-xMP2O7 (M = Fe, Co) was carried out using neutron diffraction (ND) and X-ray diffraction (XRD) analyses to elucidate structural information and structural changes during an electrochemical reaction. The crystal system and space group were determined to be monoclinic P21/c for both materials with a = 11.0192 (4) Å, b = 9.7488 (3) Å, c = 9.8057 (4) Å, and β = 101.569 (3)° for Li2-xFeP2O7 and a = 10.9574 (3), b = 9.6921 (3), c = 9.7611 (3), and β = 101.776 (2)° for Li2-xCoP2O7. XRD analysis revealed partial occupancy of iron and cobalt in the structures of Li2-xFeP 2O7 and Li2-xCoP2O7, respectively. Also, ND identified lithium positions and partial occupancies in five different Li sites of Li2-xMP2O7 (M = Fe, Co). Further ex situ XRD showed that the charging/discharging of Li 2-xFeP2O7 occurred primarily via a two-phase reaction with a slight solid solution behavior. We also demonstrated for the first time that Li2-xCoP2O7 electrodes are electrochemically active, with a redox potential of ∼5 V (versus Li).

KW - Li MPO (M = Fe Co)

KW - neutron diffraction

KW - Structural characterization

KW - X-ray diffraction

UR - https://www.scopus.com/pages/publications/80052501538

U2 - 10.1021/cm201305z

DO - 10.1021/cm201305z

M3 - Article

AN - SCOPUS:80052501538

SN - 0897-4756

VL - 23

SP - 3930

EP - 3937

JO - Chemistry of Materials

JF - Chemistry of Materials

IS - 17

ER -