title: Mapping polaronic states and lithiation gradients in individual V2O5 nanowires.
abstract: The rapid insertion and extraction of Li ions from a cathode material is imperative for the functioning of a Li-ion battery. In many cathode materials such as LiCoO2, lithiation proceeds through solid-solution formation, whereas in other materials such as LiFePO4 lithiation/delithiation is accompanied by a phase transition between Li-rich and Li-poor phases. We demonstrate using scanning transmission X-ray microscopy (STXM) that in individual nanowires of layered V2O5, lithiation gradients observed on Li-ion intercalation arise from electron localization and local structural polarization. Electrons localized on the V2O5 framework couple to local structural distortions, giving rise to small polarons that serves as a bottleneck for further Li-ion insertion. The stabilization of this polaron impedes equilibration of charge density across the nanowire and gives rise to distinctive domains. The enhancement in charge/discharge rates for this material on nanostructuring can be attributed to circumventing challenges with charge transport from polaron formation.
authors.affiliation: Department of Chemistry, Texas A&M University, Ross@Spence Street, College Station, Texas 77845-3012, USA.|Department of Materials Science and Engineering, Texas A&M University, 575 Ross Street, College Station, Texas 77843-3003, USA.
authors.forename: Luis R
authors.initials: LR
authors.lastname: De Jesus
authors.affiliation: Department of Chemistry, Texas A&M University, Ross@Spence Street, College Station, Texas 77845-3012, USA.|Department of Materials Science and Engineering, Texas A&M University, 575 Ross Street, College Station, Texas 77843-3003, USA.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Horrocks
authors.affiliation: The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Department of Chemistry, Texas A&M University, Ross@Spence Street, College Station, Texas 77845-3012, USA.|Department of Materials Science and Engineering, Texas A&M University, 575 Ross Street, College Station, Texas 77843-3003, USA.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Parija
authors.affiliation: Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Cherno
authors.initials: C
authors.lastname: Jaye
authors.affiliation: Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, New York 13902, USA.
authors.forename: Linda
authors.initials: L
authors.lastname: Wangoh
authors.affiliation: Canadian Light Source, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 2V3.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Fischer
authors.affiliation: Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, New York 13902, USA.
authors.forename: Louis F J
authors.initials: LF
authors.lastname: Piper
authors.affiliation: The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: David
authors.initials: D
authors.lastname: Prendergast
authors.affiliation: Department of Chemistry, Texas A&M University, Ross@Spence Street, College Station, Texas 77845-3012, USA.|Department of Materials Science and Engineering, Texas A&M University, 575 Ross Street, College Station, Texas 77843-3003, USA.
authors.forename: Sarbajit
authors.initials: S
authors.lastname: Banerjee