Aniline oligomer-modified graphene for enhanced electrochemical performances

Abstract The surface of graphene (Gr) was covalently attached by an aniline oligomer, from the coupling of graphene oxide with aniline tetramer, followed by reduction process. After linked by tetramer aniline, the graphene materials showed remarkably enhanced electrochemical performances. The conductivity of the graphene was increased from 5.8 S cm −1 to 41.7 S cm ‒1 , under the strong doping effect between Gr and tetramer aniline by means of the π‒π interactions, which was analyzed by FT‒IR, UV–vis and XPS spectra. In addition, the aniline oligomer attached to reduced graphene oxide (AOAG) showed a remarkable energy-storage behavior due to the synergistic effect. The capacitance of AOAGs can be 370 F g −1 , while it is 114 F g −1 and 129 F g −1 for graphene oxide and tetramer aniline respectively. Because the covalent bonding between graphene and aniline oligomer can effectively combine the excellent mechanical strength of graphene and the large faradic pseudocapacitance of aniline oligomer, the AOAGs showed quite high charge-discharge cycle stability besides remarkable capacitance. In addition, the ease of electron motion mediated by the covalent bonding in AOAGs supports the sample significant electrochemical catalysis towards nifedipine. Compared with graphene and tetramer aniline, the oxidative current of nifedipine on AOAG showed five-fold increase.