First-principles study of the mechanism of wettability transition of defective graphene

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F17%3A73583989" target="_blank" >RIV/61989592:15310/17:73583989 - isvavai.cz</a>

Výsledek na webu

<a href="http://iopscience.iop.org/article/10.1088/1361-6528/aa53c5/meta" target="_blank" >http://iopscience.iop.org/article/10.1088/1361-6528/aa53c5/meta</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6528/aa53c5" target="_blank" >10.1088/1361-6528/aa53c5</a>

Jazyk výsledku

angličtina

Název v původním jazyce

First-principles study of the mechanism of wettability transition of defective graphene

Popis výsledku v původním jazyce

Hydrophobicity of graphene limits its application potential in polar media, therefore modifications of graphene wettability have been in an area of active research for many years. Recently, a reversible wettability transition of graphene has been reported (Xu et al 2014 Sci. Rep. 4 6450). The presence of undercoordinated carbon atoms in otherwise hydrophobic graphene is believed to trigger the hydrophobic to hydrophilic transition, but the underlying mechanism, especially of the reverse process, remained unclear. Using density functional theory with range-separated hybrid functional HSE06, we investigate the dissociative adsorption of up to two water molecules on the defective graphene layer containing odd number of missing lattice atoms. We show, that depending on the defect type either a full dissociation of the water molecule or a partial splitting of H2O to OH and H takes place leading to the saturation of graphene dangling bonds due to the formation of oxiranes or by hydroxyls, respectively. The dissociation barriers are significantly lower for the water dimer than for the single molecule. Our findings providing detailed insights into the remarkable differences between the reactivity of vacancy defects with water shed new light on the wettability-transition mechanism of defective graphene.

Název v anglickém jazyce

First-principles study of the mechanism of wettability transition of defective graphene

Popis výsledku anglicky

Hydrophobicity of graphene limits its application potential in polar media, therefore modifications of graphene wettability have been in an area of active research for many years. Recently, a reversible wettability transition of graphene has been reported (Xu et al 2014 Sci. Rep. 4 6450). The presence of undercoordinated carbon atoms in otherwise hydrophobic graphene is believed to trigger the hydrophobic to hydrophilic transition, but the underlying mechanism, especially of the reverse process, remained unclear. Using density functional theory with range-separated hybrid functional HSE06, we investigate the dissociative adsorption of up to two water molecules on the defective graphene layer containing odd number of missing lattice atoms. We show, that depending on the defect type either a full dissociation of the water molecule or a partial splitting of H2O to OH and H takes place leading to the saturation of graphene dangling bonds due to the formation of oxiranes or by hydroxyls, respectively. The dissociation barriers are significantly lower for the water dimer than for the single molecule. Our findings providing detailed insights into the remarkable differences between the reactivity of vacancy defects with water shed new light on the wettability-transition mechanism of defective graphene.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

21002 - Nano-processes (applications on nano-scale); (biomaterials to be 2.9)

Projekt

<a href="/cs/project/LO1305" target="_blank" >LO1305: Rozvoj centra pokročilých technologií a materiálů</a><br>

Návaznosti

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

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Nanotechnology

ISSN

0957-4484

e-ISSN

—

Svazek periodika

28

Číslo periodika v rámci svazku

6

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

7

Strana od-do

064003

Kód UT WoS článku

000393778400001

EID výsledku v databázi Scopus

—