On oxygen-containing groups in chemically modified graphenes

Alessandra Bonanni, Adriano Ambrosi, Martin Pumera

Research output: Contribution to journalArticlepeer-review

67 Citations (Scopus)


Reduced graphenes (belonging to the class of chemically modified graphenes, CMG) are one of the most investigated and utilized materials in current research. Oxygen functionalities on the CMG surfaces have dramatic influences on material properties. Interestingly, these functionalities are rarely comprehensively characterized. Herein, the four most commonly used CMGs, mainly electrochemically reduced graphene oxide (ER-GO), thermally reduced graphene oxide (TR-GO), and the corresponding starting materials, that is, graphene oxide and graphite oxide, were comprehensively characterized by a wide variety of methods, such as high-resolution X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, UV/Vis spectroscopy, transmission electron microscopy (TEM), and voltammetry, to establish connections between the structures of these materials that carry different oxygen functionalities and their electrochemical behaviors. This was followed by the quantification of the negatively charged oxygen-containing groups (OCGs) by UV/Vis spectroscopy and of the electrochemically reducible OCGs by voltammetry. Lastly, a biofunctionalization with gold nanoparticle (AuNP)-modified DNA sequences was performed by the formation of covalent bonds with the carboxylic groups (-COOH) on the CMG surfaces. There was an evident predominance of functionalizable -COOH groups on the ER-GO surface, as confirmed by a higher amount of Au detected both with differential-pulse voltammetry and impedance spectroscopy, coupled with visualization by TEM. We exploited the DNA-Au bioconjugates as highly specific stains to localize and visualize the positions of carboxylic groups. Our findings are very important to clearly identify the presence, nature, and distribution of oxygen functionalities on different chemically modified graphenes.

Original languageEnglish
Pages (from-to)4541-4548
Number of pages8
JournalChemistry - A European Journal
Issue number15
Publication statusPublished - 2012 Apr 10

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Organic Chemistry


Dive into the research topics of 'On oxygen-containing groups in chemically modified graphenes'. Together they form a unique fingerprint.

Cite this