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Role of peroxide ions in formation of graphene nanosheets by electrochemical exfoliation of graphite.

ABSTRACT: This study demonstrates a facile, mild and environmentally-friendly sustainable (soft processing) approach for the efficient electrochemical exfoliation of graphite using a sodium hydroxide/hydrogen peroxide/water (NaOH/H2O2/H2O) system that can produce high-quality, anodic few-layer graphene nanosheets in 95% yield at ambient reaction conditions. The control experiment conducted using NaOH/H2O revealed the crucial role of H2O2 in the exfoliation of graphite. A possible exfoliation mechanism is proposed. The reaction of H2O2 with hydroxyl ions (HO(-)) leads to the formation of highly nucleophilic peroxide ions (O2(2-)), which play a crucial role in the exfoliation of graphite via electrochemical-potential-assisted intercalation and strong expansion of graphite sheets.

SUBMITTER: Rao KS

PROVIDER: S-EPMC3937785 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Role of peroxide ions in formation of graphene nanosheets by electrochemical exfoliation of graphite.

Rao Kodepelly Sanjeeva KS Senthilnathan Jaganathan J Liu Yung-Fang YF Yoshimura Masahiro M

Scientific reports 20140228

This study demonstrates a facile, mild and environmentally-friendly sustainable (soft processing) approach for the efficient electrochemical exfoliation of graphite using a sodium hydroxide/hydrogen peroxide/water (NaOH/H2O2/H2O) system that can produce high-quality, anodic few-layer graphene nanosheets in 95% yield at ambient reaction conditions. The control experiment conducted using NaOH/H2O revealed the crucial role of H2O2 in the exfoliation of graphite. A possible exfoliation mechanism is ...[more]

PMID: 24577336

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