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Modification of Graphitic Carbon Nitride with Hydrogen Peroxide.

ABSTRACT: Graphitic carbon nitride (GCN) was synthetized by heating melamine and then it was thermally exfoliated for 1-3 h in air. Both bulk and exfoliated GCN nanomaterials were treated in the 10-30% aqueous solutions of H2O2 for us to study their modification. The light absorption properties were observed by the reddish color and the red-shifts of their UV-Vis spectra. The content of oxygen increased and hydrogen peroxide was supposed to partially oxidize C-OH groups to C=O ones and to form C-O-C groups instead of edge C-NH-C ones. The GCN structure changes were not observed. However, a surface modification of the GCN materials was recognized by their changed photocatalytic activities tested by means of Acid Orange 7 (AO7) and Rhodamines B (RhB), zeta-potentials, and neutralization titration curves.

SUBMITTER: Praus P

PROVIDER: S-EPMC7559342 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Modification of Graphitic Carbon Nitride with Hydrogen Peroxide.

Praus Petr P Smýkalová Aneta A Foniok Kryštof K Matějka Vlastimil V

Nanomaterials (Basel, Switzerland) 20200903 9

Graphitic carbon nitride (GCN) was synthetized by heating melamine and then it was thermally exfoliated for 1-3 h in air. Both bulk and exfoliated GCN nanomaterials were treated in the 10-30% aqueous solutions of H<sub>2</sub>O<sub>2</sub> for us to study their modification. The light absorption properties were observed by the reddish color and the red-shifts of their UV-Vis spectra. The content of oxygen increased and hydrogen peroxide was supposed to partially oxidize C-OH groups to C=O ones a ...[more]

PMID: 32899275

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