Electrochemical investigations of Pu(IV)/Pu(III) redox reaction using graphene modified glassy carbon electrodes and a comparison to the performance of SWCNTs modified glassy carbon electrodes

•First report of aqueous electrochemistry of Plutonium on graphene modified electrode.•Graphene is best electrocatalytic material for Pu(IV)/Pu(III) redox couple among the reported modifiers viz. reduced graphene oxide (rGO) and SWCNT’s.•The electrochemical reversibility of Pu(IV)/Pu(III) redox couple improves significantly on graphene modified electrode compared to previously reported rGO & SWCNTs modified electrodes•Donnan interaction between plutonium species and graphene surface offers a possibility for designing a highly sensitive sensor for plutonium•Graphene modified electrode shows higher sensitivity for the determination of plutonium compared to glassy carbon and single walled carbon nanotube modified electrode The work reported in this paper demonstrates for the first time that graphene modified glassy carbon electrode (Gr/GC) show remarkable electrocatalysis towards Pu(IV)/Pu(III) redox reaction and the results were compared with that of single-walled carbon nanotubes modified GC (SWCNTs/GC) and glassy carbon (GC) electrodes. Graphene catalyzes the exchange of current of the Pu(IV)/Pu(III) couple by reducing both the anodic and cathodic overpotentials. The Gr/GC electrode shows higher peak currents (ip) and smaller peak potential separation (ΔEp) values than the SWCNTs/GC and GC electrodes. The heterogeneous electron transfer rate constants (ks), charge transfer coefficients (α) and the diffusion coefficients (D) involved in the electrocatalytic redox reaction were determined. Our observations show that graphene is best electrocatalytic material among both the SWCNTs and GC to study Pu(IV)/Pu(III) redox reaction.