Faculty Publications

V2O5: A 2D Van Der Waals Oxide With Strong In-Plane Electrical And Optical Anisotropy

Document Type

Article

Keywords

2D material, anisotropy, Raman, transport, vanadium pentoxide

Journal/Book/Conference Title

ACS Applied Materials and Interfaces

Volume

9

Issue

28

First Page

23949

Last Page

23956

Abstract

V2O5 with a layered van der Waals (vdW) structure has been widely studied because of the material's potential in applications such as battery electrodes. In this work, microelectronic devices were fabricated to study the electrical and optical properties of mechanically exfoliated multilayered V2O5 flakes. Raman spectroscopy was used to determine the crystal structure axes of the nanoflakes and revealed that the intensities of the Raman modes depend strongly on the relative orientation between the crystal axes and the polarization directions of incident/scattered light. Angular dependence of four-probe resistance measured in the van der Pauw (vdP) configuration revealed an in-plane anisotropic resistance ratio of ∼100 between the a and b crystal axes, the largest in-plane transport anisotropy effect experimentally reported for two-dimensional (2D) materials to date. This very large resistance anisotropic ratio is explained by the nonuniform current flow in the vdP measurement and an intrinsic mobility anisotropy ratio of 10 between the a and b crystal axes. Room-temperature electron Hall mobility up to 7 cm2/(V s) along the high-mobility direction was obtained. This work demonstrates V2O5 as a layered 2D vdW oxide material with strongly anisotropic optical and electronic properties for novel applications.

Department

Department of Physics

Original Publication Date

7-19-2017

DOI of published version

10.1021/acsami.7b05377

Repository

UNI ScholarWorks, Rod Library, University of Northern Iowa

Language

en

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