Synthesis and electrochemical studies of Ta - Graphene nanocomposite film modified platinum electrode

•Nanocarbon electrode based supercapacitors exhibits high efficiency.•Metal oxide with multiple oxidation states shows remarkable pseudocapacitive nature.•The areal capacitance value of Ta doped reduced graphene oxide is 1420 μF/cm2.•The cyclic stability of metal oxide/nanocarbon composite is higher.

Tantalum/Reduced Graphene Oxide composite is presented in this work as an electrode material for capacitor application. Reduced graphene oxide material was synthesized by modified Hummer's method and Tantalum doped graphene oxide electrodes are fabricated by an electrophoretic deposition method. The physico-chemical properties of the as-synthesized materials are characterized by X-ray diffraction, N2 sorption analyses, Fourier Transform Infrared and Raman spectroscopic techniques. The structural details are elucidated from the scanning and transmission electron microscopic analyses. The X-ray diffraction results confirmed the structural integrity of graphene after the Ta doping process. Raman analysis confirmed the graphitic nature of graphene with a surface area of 281 m2/g. The surface area of the tantalum doped composite decreased to 214 m2/g due to the deposition of Ta ions onto the graphene surface. The Ta doped graphene composite exhibited comparatively higher capacitance value of 1420 μF/cm2 than graphene (980 μF/cm2), indicating that this composite can store more charge in comparison with graphene. This enhancement of capacitance with Ta doped graphene is thus found to be a good candidate for super/ultra capacitor applications