Cold cathode emission studies on topographically modified few layer and single layer MoS2 films
Artikel i vetenskaplig tidskrift, 2016

Nanostructured materials, such as carbon nanotubes, are excellent cold cathode emitters. Here, we report comparative field emission (FE) studies on topographically tailored few layer MoS2films consisting of ⟨0001⟩ plane perpendicular (⊥) to c-axis (i.e., edge terminated vertically aligned) along with planar few layer and monolayer (1L) MoS2films. FE measurements exhibited lower turn-on field Eto (defined as required applied electric field to emit current density of 10 μA/cm2) ∼4.5 V/μm and higher current density ∼1 mA/cm2, for edge terminated vertically aligned (ETVA) MoS2films. However, Eto magnitude for planar few layer and 1L MoS2films increased further to 5.7 and 11 V/μm, respectively, with one order decrease in emission current density. The observed differences in emission behavior, particularly for ETVA MoS2 is attributed to the high value of geometrical field enhancement factor (β), found to be ∼1064, resulting from the large confinement of localized electric field at edge exposed nanograins. Emission behavior of planar few layers and 1L MoS2films are explained under a two step emission mechanism. Our studies suggest that with further tailoring the microstructure of ultra thin ETVA MoS2films would result in elegant FE properties.

Författare

A.P.S. Gaur

University of Puerto Rico

S. Sahoo

University of Puerto Rico

Institute of Physics Bhubaneswar

F. Mendoza

University of Puerto Rico

A.M. Rivera

University of Puerto Rico

M. Kumar

Institute of Physics Bhubaneswar

Saroj Prasad Dash

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

G. Morell

University of Puerto Rico

R.S. Katiyar

University of Puerto Rico

Applied Physics Letters

0003-6951 (ISSN) 1077-3118 (eISSN)

Vol. 108 4 043103- 043103

Styrkeområden

Nanovetenskap och nanoteknik

Energi

Materialvetenskap

Ämneskategorier

Fysik

Fundament

Grundläggande vetenskaper

DOI

10.1063/1.4940306