Probing the charge transfer and electron-hole asymmetry in graphene-graphene quantum dot heterostructure

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F22%3APU144921" target="_blank" >RIV/00216305:26620/22:PU144921 - isvavai.cz</a>

Alternative codes found

RIV/00216224:14310/22:00128664

Result on the web

<a href="https://iopscience.iop.org/article/10.1088/1361-6528/ac6c38" target="_blank" >https://iopscience.iop.org/article/10.1088/1361-6528/ac6c38</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6528/ac6c38" target="_blank" >10.1088/1361-6528/ac6c38</a>

Result language

angličtina

Original language name

Probing the charge transfer and electron-hole asymmetry in graphene-graphene quantum dot heterostructure

Original language description

In recent years, graphene-based van der Waals (vdW) heterostructures have come into prominence showcasing interesting charge transfer dynamics which is significant for optoelectronic applications. These novel structures are highly tunable depending on several factors such as the combination of the two-dimensional materials, the number of layers and band alignment exhibiting interfacial charge transfer dynamics. Here, we report on a novel graphene based 0D-2D vdW heterostructure between graphene and amine-functionalized graphene quantum dots (GQD) to investigate the interfacial charge transfer and doping possibilities. Using a combination of ab initio simulations and Kelvin probe force microscopy (KPFM) measurements, we confirm that the incorporation of functional GQDs leads to a charge transfer induced p-type doping in graphene. A shift of the Dirac point by 0.05 eV with respect to the Fermi level (E (F)) in the graphene from the heterostructure was deduced from the calculated density of states. KPFM measurements revealed an increment in the surface potential of the GQD in the 0D-2D heterostructure by 29 mV with respect to graphene. Furthermore, we conducted power dependent Raman spectroscopy for both graphene and the heterostructure samples. An optical doping-induced gating effect resulted in a stiffening of the G band for electrons and holes in both samples (graphene and the heterostructure), suggesting a breakdown of the adiabatic Born-Oppenheimer approximation. Moreover, charge imbalance and renormalization of the electron-hole dispersion under the additional influence of the doped functional GQDs is pointing to an asymmetry in conduction and carrier mobility.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

21000 - Nano-technology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

NANOTECHNOLOGY

ISSN

0957-4484

e-ISSN

1361-6528

Volume of the periodical

33

Issue of the periodical within the volume

32

Country of publishing house

GB - UNITED KINGDOM

Number of pages

9

Pages from-to

„325704-1“-„325704-9“

UT code for WoS article

000798066500001

EID of the result in the Scopus database

2-s2.0-85130862829