Synthesis of Carboxylated-Graphenes by the Kolbe-Schmitt Process

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F17%3A43913398" target="_blank" >RIV/60461373:22310/17:43913398 - isvavai.cz</a>

Výsledek na webu

<a href="http://pubs.acs.org/doi/abs/10.1021/acsnano.6b07746" target="_blank" >http://pubs.acs.org/doi/abs/10.1021/acsnano.6b07746</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acsnano.6b07746" target="_blank" >10.1021/acsnano.6b07746</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Synthesis of Carboxylated-Graphenes by the Kolbe-Schmitt Process

Popis výsledku v původním jazyce

Graphene oxide is an oxidized form of graphene containing a large variety of oxygen groups. Although past models have suggested carboxylic acids to be present in significant amounts, recent evidence has shown otherwise. Toward the production of carboxyl-graphene, a synthetic method is presented herein based on the Kolbe- Schmitt process. A modified procedure of heating graphite oxide in the presence of a KOH/CaO mixture results in up to 11 atom % of carboxylic groups. The graphite oxide starting material and reaction temperature were investigated as two important factors, where a crumpled morphology of graphite oxide flakes and a lower 220 degrees C temperature preferentially led to greater carboxyl functionalization. Successful carboxylation caused a band gap opening of similar to 2.5 eV in the smallest carboxyl graphene particles, which also demonstrated a yellow fluorescence under UV light unseen in its counterpart produced at 500 degrees C. These results are in good agreement with theoretical calculations showing band gap opening and spin polarization of impurity states. This demonstrates the current synthetic process as yet another approach toward tuning the physical properties of graphene.

Název v anglickém jazyce

Synthesis of Carboxylated-Graphenes by the Kolbe-Schmitt Process

Popis výsledku anglicky

Graphene oxide is an oxidized form of graphene containing a large variety of oxygen groups. Although past models have suggested carboxylic acids to be present in significant amounts, recent evidence has shown otherwise. Toward the production of carboxyl-graphene, a synthetic method is presented herein based on the Kolbe- Schmitt process. A modified procedure of heating graphite oxide in the presence of a KOH/CaO mixture results in up to 11 atom % of carboxylic groups. The graphite oxide starting material and reaction temperature were investigated as two important factors, where a crumpled morphology of graphite oxide flakes and a lower 220 degrees C temperature preferentially led to greater carboxyl functionalization. Successful carboxylation caused a band gap opening of similar to 2.5 eV in the smallest carboxyl graphene particles, which also demonstrated a yellow fluorescence under UV light unseen in its counterpart produced at 500 degrees C. These results are in good agreement with theoretical calculations showing band gap opening and spin polarization of impurity states. This demonstrates the current synthetic process as yet another approach toward tuning the physical properties of graphene.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10402 - Inorganic and nuclear chemistry

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

2017

Kód důvěrnosti údajů

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

Název periodika

ACS Nano

ISSN

1936-0851

e-ISSN

—

Svazek periodika

11

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

1789-1797

Kód UT WoS článku

000395357300072

EID výsledku v databázi Scopus

2-s2.0-85014240693