High-performance supercabattery based on reduced graphene oxide/metal organic framework nanocomposite decorated with palladium nanoparticles

Reduced graphene oxide/metal organic framework nanocomposite decorated with palladium nanoparticles (Pd-rGO/MOF) was studied as an efficient electrode material for energy storage applications using nickel foam (NF) as a current collector and aqueous 3.0 M KOH as electrolyte. Pd-rGO/MOF nanocomposite showed a morphology in which a thin layer of rGO coating existed over MOF with unique bright spots indicating the presence of Pd nanoparticles. The synthesised materials were analysed by cyclic voltammetry (CV), electrochemical impedance spectrometry (EIS), and galvanostatic charge-discharge (GCD) for application in supercabattery. The Pd-rGO/ MOF nanocomposite displayed improved electron transfer kinetics and superior battery-type performance with a large specific capacity of 712.0 C g(-1) at 2.0 A g(-1) in a three-electrode system. Furthermore, Pd-rGO/MOF nanocomposite exhibited high electrochemical performance when applied as a positive electrode and activated carbon (AC) as a negative electrode in an asymmetric, two-electrode system, configuration. The AC//Pd-rGO/ MOF displayed an excellent maximum energy density of 26.0 Wh kg(-1) (at 0.6 A g(-1)), power density of 1600 W kg(-1) (at 2.0 A g(-1)), and good charge-discharge stability after 3500 cycles. This highlights the impact of Pd nanoparticles on the rGO/MOF nanocomposite for energy storage applications in supercabattery.