In-Situ XAS Investigation of the Effect of Electrochemical Reactions on the Structure of Graphene in Aqueous Electrolytes.

In-situ X-ray Absorption Spectroscopy (XAS), Raman Spectroscopy, AFM and XPS have been used to investigate the effect of reactions occurring in aqueous electrolytes on the structure of a single-layer graphene produced by CVD. It was found that defects are readily and irreversibly produced by application of electrode voltages. The defects and the products were identified also by new features in the XAS spectra. Our findings show the poor stability of the CVD graphene, which could be a challenge in applications such as super-capacitors, fuel-cells, batteries and photo-catalysis. [ABSTRACT FROM AUTHOR]