Structural evolution of functionalized graphene sheets during solvothermal reduction

Solvothermally reduced and functionalized graphene (SRFG) was obtained by refluxing graphene oxide in dimethyl formamide at 140 °C. The resultant simultaneous nitrogen-doping and presence of dangling bonds on SRFG prompted us to study the evolution of structural changes with refluxing time. It is shown that the removal of oxygen-containing functional groups leaves dangling bonds during the solvothermal reduction, which are responsible for the nitrogen-doping with longer refluxing time. The relationship between the defects of SRFGs and their lithium ion storage performances are also discussed.