title: Correlation between the O 2p Orbital and Redox Reaction in LiMn0.6Fe0.4PO4Nanowires Studied by Soft X-ray Absorption.
abstract: The changes in the electronic structure of LiMn0.6Fe0.4PO4nanowires during discharge processes were investigated by using ex situ soft X-ray absorption spectroscopy. The Fe L-edge X-ray absorption spectrum attributes the potential plateau at 3.45 V versus Li/Li+of the discharge curve to a reduction of Fe3+to Fe2+. The Mn L-edge X-ray absorption spectra exhibit the Mn2+multiplet structure throughout the discharge process, and the crystal-field splitting was slightly enhanced upon full discharge. The configuration-interaction full-multiplet calculation for the X-ray absorption spectra reveals that the charge-transfer effect from O 2p to Mn 3d orbitals should be considerably small, unlike that from the O 2p to Fe 3d orbitals. Instead, the O K-edge X-ray absorption spectrum shows a clear spectral change during the discharge process, suggesting that the hybridization of O 2p orbitals with Fe 3d orbitals contributes essentially to the reduction.
authors.affiliation: Research Institute for Energy Conservation, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Asakura
authors.affiliation: Research Institute for Energy Conservation, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Hosono
authors.affiliation: Research Institute for Energy Conservation, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.|Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Okubo
authors.affiliation: Research Institute for Energy Conservation, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.|INAMORI Frontier Research Center, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nanba
authors.affiliation: Research Institute for Energy Conservation, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.
authors.forename: Haoshen
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS6R2100, Berkeley, California, 94720, USA.
authors.forename: Per-Anders
authors.initials: PA
authors.lastname: Glans
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS6R2100, Berkeley, California, 94720, USA.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Guo
keywords: cathode materials; lithium-ion batteries; olivine; redox reactions; soft X-ray absorption spectroscopy