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Single graphene nanoplatelets: capacitance, potential of zero charge and diffusion coefficient.

ABSTRACT: Nano-impact chronoamperometric experiments are a powerful technique for simultaneously probing both the potential of zero charge (PZC) and the diffusion coefficient (D₀) of graphene nanoplatelets (GNPs). The method provides an efficient general approach to material characterisation. Using nano-impact experiments, capacitative impacts can be seen for graphene nanoplatelets of 15 ?m width and 6-8 nm thickness. The current transient features seen allow the determination of the PZC of the graphene nanoplatelet in PBS buffer as -0.14 ± 0.03 V (vs. saturated calomel electrode). The diffusion coefficient in the same aqueous medium, isotonic with many biological conditions, for the graphene nanoplatelets is experimentally found to be 2 ± 0.8 × 10^-13 m² s^-1. This quick characterisation technique may significantly assist the application of graphene nanoplatelets, or similar nano-materials, in electronic, sensor, and clinical medicinal technologies.

SUBMITTER: Poon J

PROVIDER: S-EPMC5490005 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Single graphene nanoplatelets: capacitance, potential of zero charge and diffusion coefficient.

Poon Jeffrey J Batchelor-McAuley Christopher C Tschulik Kristina K Compton Richard G RG

Chemical science 20150304 5

Nano-impact chronoamperometric experiments are a powerful technique for simultaneously probing both the potential of zero charge (PZC) and the diffusion coefficient (<i>D</i><sub>0</sub>) of graphene nanoplatelets (GNPs). The method provides an efficient general approach to material characterisation. Using nano-impact experiments, capacitative impacts can be seen for graphene nanoplatelets of 15 μm width and 6-8 nm thickness. The current transient features seen allow the determination of the PZC ...[more]

PMID: 28706674

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