Loading…
Thickness-Insensitive Properties of α-MoO 3 Nanosheets by Weak Interlayer Coupling
van der Waals (vdW) materials have shown unique electrical and optical properties depending on the thickness due to strong interlayer interaction and symmetry breaking at the monolayer level. In contrast, the study of electrical and tribological properties and their thickness-insensitivity of van de...
Saved in:
Published in: | Nano letters 2019-12, Vol.19 (12), p.8868-8876 |
---|---|
Main Authors: | , , , , , |
Format: | Article |
Language: | English |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | van der Waals (vdW) materials have shown unique electrical and optical properties depending on the thickness due to strong interlayer interaction and symmetry breaking at the monolayer level. In contrast, the study of electrical and tribological properties and their thickness-insensitivity of van der Waals oxides are lacking due to difficulties in the fabrication of high quality two-dimensional oxides and the investigation of nanoscale properties. Here we investigated various tribological and electrical properties, such as, friction, adhesion, work function, tunnel current, and dielectric constant, of the single-crystal α-MoO
nanosheets epitaxially grown on graphite by using atomic force microscopy. The friction of atomically smooth MoO
is rapidly saturated within a few layers. The thickness insensitivity of friction is due to very weak mechanical interlayer interaction. Similarly, work function (4.73 eV for 2 layers (hereafter denoted as L)) and dielectric constant (6 for 2L and 10.5-11 for >3L) of MoO
in MoO
showed thickness insensitivity due to weak interlayer coupling. Tunnel current measurements by conductive atomic force microscopy showed that even 2L MoO
of 1.4 nm is resistant to tunneling with a high dielectric strength of 14 MV/cm. The thickness-indifferent electrical properties of high dielectric constant and tunnel resistance by weak interlayer coupling and high crystallinity show a promise in the use of MoO
nanosheets for nanodevice applications. |
---|---|
ISSN: | 1530-6984 1530-6992 |
DOI: | 10.1021/acs.nanolett.9b03701 |