Defect healing of reduced graphene oxide via intramolecular cross-dehydrogenative coupling

Abstract

A chemical defect healing of reduced graphene oxide (RGO) was carried out via intramolecular cross-dehydrogenative coupling (ICDC) with FeCl3 at room temperature. The Raman intensity ratio of the G-band to the D-band, the I-G/I-D ratio, of the RGO was increased from 0.77 to 1.64 after the ICDC reaction. From XPS measurements, the A(C=C)/A(C-C) ratio, where the peak intensities from the C=C and C-C bonds are abbreviated as A(C=C) and A(C-C), of the RGO was increased from 2.88 to 3.79. These results demonstrate that the relative amount of sp(2)-hybridized carbon atoms is increased by the ICDC reaction. It is of great interest that after the ICDC reaction the electrical conductivity of the RGO was improved to 71 S cm(-1), which is 14 times higher than that of as-prepared RGO (5 S cm(-1)).