Hydrogenated Graphenes by Birch Reduction: Influence of Electron and Proton Sources on Hydrogenation Efficiency, Magnetism, and Electrochemistry

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F15%3A43899789" target="_blank" >RIV/60461373:22310/15:43899789 - isvavai.cz</a>

Alternative codes found

RIV/68378271:_____/15:00456309

Result on the web

<a href="http://onlinelibrary.wiley.com/doi/10.1002/chem.201503219/full" target="_blank" >http://onlinelibrary.wiley.com/doi/10.1002/chem.201503219/full</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/chem.201503219" target="_blank" >10.1002/chem.201503219</a>

Result language

angličtina

Original language name

Hydrogenated Graphenes by Birch Reduction: Influence of Electron and Proton Sources on Hydrogenation Efficiency, Magnetism, and Electrochemistry

Original language description

Interest in chemical functionalisation of graphenes today is largely driven by associated changes to its physical and material properties. Functionalisation with hydrogen was employed to obtain hydrogenated graphenes (also termed graphane if fully hydrogenated), which exhibited properties including fluorescence, magnetism and a tuneable band gap. Although the classical Birch reduction has been employed for hydrogenation of graphite oxide, variation exists between the choice of alkali metals and alcohols/water as quenching agents. A systematic study of electron (Li, Na, K, Cs) and proton sources (tBuOH, iPrOH, MeOH, H2O) has been performed to identify optimal conditions. The proton source exerted a great influence on the resulting hydrogenation with water and out-performed alcohols, and the lowest carbon-to-hydrogen ratio was observed with sodium and water with composition of C1.4H1O0.3. Although ferromagnetism at room temperature correlates well with increasing hydrogen concentrations, small contributions from trace iron impurities cannot be completely eliminated. In contrast, hydrogenated graphenes exhibit a significant paramagnetic moment at low temperatures that has no correlation with impurities, and therefore, originates from the carbon system. This is in comparison to graphene, which is strongly diamagnetic, and concentrations of paramagnetic centres in hydrogenated graphenes are one order of magnitude larger than that in graphite. Nonetheless, hydrogenation over a particular level might also excessively disrupt intrinsic sp(2) conjugation, resulting in unintended reduction of electrochemical properties. This was observed with heterogeneous electron-transfer rates and it was postulated that hydrogenated graphenes should generally have high defect densities, but only moderately high hydrogenation, should they be employed as electrode materials.

Czech name

—

Czech description

—

Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

CA - Inorganic chemistry

OECD FORD branch

—

Project

<a href="/en/project/GA15-09001S" target="_blank" >GA15-09001S: Chemical modifications of graphene based materials: Synthesis of graphane and halogengraphene</a><br>

Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2015

Confidentiality

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

Name of the periodical

Chemistry A European Journal

ISSN

0947-6539

e-ISSN

—

Volume of the periodical

21

Issue of the periodical within the volume

47

Country of publishing house

DE - GERMANY

Number of pages

11

Pages from-to

16828-16838

UT code for WoS article

000366501600017

EID of the result in the Scopus database

—