High quality reduced graphene oxide flakes by fast kinetically controlled and clean indirect UV-induced radical reduction
Artikel i vetenskaplig tidskrift, 2016

This work highlights a surprisingly simple and kinetically controlled highly efficient indirect method for the production of high quality reduced graphene oxide (rGO) flakes via UV irradiation of aqueous dispersions of graphene oxide (GO), in which the GO is not excited directly. While the direct photoexcitation of aqueous GO (when GO is the only light-absorbing component) takes several hours of reaction time at ambient temperature (4 h) leading only to a partial GO reduction, the addition of small amounts of isopropanol and acetone (2% and 1%) leads to a dramatically shortened reaction time by more than two orders of magnitude (2 min) and a very efficient and soft reduction of graphene oxide. This method avoids the formation of non-volatile species and in turn contamination of the produced rGO and it is based on the highly efficient generation of reducing carbon centered isopropanol radicals via the reaction of triplet acetone with isopropanol. While the direct photolysis of GO dispersions easily leads to degradation of the carbon lattice of GO and thus to a relatively low electric conductivity of the films of flakes, our indirect photoreduction of GO instead largely avoids the formation of defects, keeping the carbon lattice intact. Mechanisms of the direct and indirect photoreduction of GO have been elucidated and compared. Raman spectroscopy, XPS and conductivity measurements prove the efficiency of the indirect photoreduction in comparison with the state-of-the-art reduction method for GO (hydriodic acid/trifluoroacetic acid). The rapid reduction times and water solvent containing only small amounts of isopropanol and acetone may allow easy process up-scaling for technical applications and low-energy consumption.

1973

Chemistry

functionalization

carbon framework

p1462

aqueous-solution

v69

p5698

1988

solid-state nmr

graphite oxide

Physics

huchmann mn

defects

chemical-reduction

journal of the american chemical society

Science & Technology - Other Topics

rter g

chemistry

acetone

v110

Materials Science

rate constants

journal of the chemical society-faraday transactions i

Författare

R. Flyunt

Institut fur Oberflachenmodifizierung Leipzig eV

W. Knolle

Institut fur Oberflachenmodifizierung Leipzig eV

Axel Kahnt

Friedrich-Alexander-Universität Erlangen Nurnberg (FAU)

C. E. Halbig

Friedrich-Alexander-Universität Erlangen Nurnberg (FAU)

A. Lotnyk

Institut fur Oberflachenmodifizierung Leipzig eV

T. Haupl

Institut fur Oberflachenmodifizierung Leipzig eV

A. Prager

Institut fur Oberflachenmodifizierung Leipzig eV

Siegfried Eigler

Chalmers, Kemi och kemiteknik

B. Abel

Institut fur Oberflachenmodifizierung Leipzig eV

Nanoscale

2040-3364 (ISSN)

Vol. 8 14 7572-7579

Styrkeområden

Nanovetenskap och nanoteknik

Ämneskategorier

Nanoteknik

Kemi

DOI

10.1039/c6nr00156d

Mer information

Senast uppdaterat

2018-03-29