Unveiling the true band gap of fluorographene and its origins by teaming theory and experiment

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15640%2F22%3A73618661" target="_blank" >RIV/61989592:15640/22:73618661 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989100:27740/22:10249752 RIV/61989100:27640/22:10249752

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0169433222004172?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0169433222004172?via%3Dihub</a>

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

Unveiling the true band gap of fluorographene and its origins by teaming theory and experiment

Popis výsledku v původním jazyce

Fluorographene is a fully fluorinated derivative of graphene. Unlike graphene, fluorographene is a wide gap semiconductor/insulator that holds great potential for applications requiring two-dimensional dielectric nanomaterials. Despite growing interest and a well-defined structure, the basic questions of fluorographene&apos;s band gap nature and value remain a conundrum. Here, we resolve this long-standing issue, demonstrating a direct optical band gap at 5.75 eV by means of diffuse reflectance spectroscopy. The nature of the band gap and the factors contributing to earlier controversies are explained by combining spectroscopic methods, ab initio calculations based on the finite momentum Bethe-Salpeter equation, and structural characterization via x-ray diffraction and Raman scattering. Ab initio calculations complement the experimental results by showing an excitonic peak at 5.65 eV of a Frenkel exciton bound to a single atom. The calculations also reveal that the absorption bands at lower energies arise from the presence of fluorine vacancies in the material, which explains earlier controversies in the literature about the band gap of fluorographene

Název v anglickém jazyce

Unveiling the true band gap of fluorographene and its origins by teaming theory and experiment

Popis výsledku anglicky

Fluorographene is a fully fluorinated derivative of graphene. Unlike graphene, fluorographene is a wide gap semiconductor/insulator that holds great potential for applications requiring two-dimensional dielectric nanomaterials. Despite growing interest and a well-defined structure, the basic questions of fluorographene&apos;s band gap nature and value remain a conundrum. Here, we resolve this long-standing issue, demonstrating a direct optical band gap at 5.75 eV by means of diffuse reflectance spectroscopy. The nature of the band gap and the factors contributing to earlier controversies are explained by combining spectroscopic methods, ab initio calculations based on the finite momentum Bethe-Salpeter equation, and structural characterization via x-ray diffraction and Raman scattering. Ab initio calculations complement the experimental results by showing an excitonic peak at 5.65 eV of a Frenkel exciton bound to a single atom. The calculations also reveal that the absorption bands at lower energies arise from the presence of fluorine vacancies in the material, which explains earlier controversies in the literature about the band gap of fluorographene

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

21001 - Nano-materials (production and properties)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

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

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

APPLIED SURFACE SCIENCE

ISSN

0169-4332

e-ISSN

1873-5584

Svazek periodika

587

Číslo periodika v rámci svazku

June

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

7

Strana od-do

"nečíslováno"

Kód UT WoS článku

000776610200002

EID výsledku v databázi Scopus

2-s2.0-85125638917