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Development of electrode materials for energy storage, with high energy and power densities along with good cyclic stability, still remains a big challenge. Here we report synthesis of Nb2O5/graphene nanocomposites through simple hydrothermal method, with Nb2O5 nanoparticles anchored on reduced graphene oxide (RGO) sheets. The fabricated Nb2O5/graphene electrodes exhibited excellent electrochemical performance when studied as anodes for Lithium-ion battery, with superior reversible capacity and high power capability (192 mAhg -1 under 0.1C rate over 50 cycles). Signature curve' studies showed high power capability of Nb2O5/graphene electrode with ~80% of the total capacity retained at 16C rate compared to ~30% retention for pristine Nb2O5 nanoparticles. To achieve further improvement in energy density and power capability, Li-ion hybrid electrochemical capacitors (Li-HEC) are fabricated with Nb2O5/graphene nanocomposite as anode and rice husk-derived activated porous carbon as cathode, in non-aqueous electrolyte. The Li-HEC showed enhanced electrochemical performances with high energy density of 30 WhKg -1 , at specific power density of 500 WKg -1 . The Nb2O5/graphene nanocomposites show promising results and hence have great potential for application in efficient electrochemical energy storage devices.

A reduced graphene oxide (rGO)‐based 3D architecture with unique flower‐like cobalt oxide microstructures, uniformly embedded in a graphene hydrogel matrix (CoO–GHG) resulting in completely interconnected structures, is fabricated. The self‐assembled 3D architecture with improved porosity and conductivity exhibits excellent electrochemical performance as an anode for lithium‐ion batteries, with high reversible specific capacity (1010 mAh g−1 over 100 cycles), a long cycling lifetime, and good rate capability. The exceptional performance results from the unique 3D structure of the hybrid CoO–GHG, with highly dispersed flower‐like CoO on a conducting graphene network, providing more accessible surface sites for large lithiation/delithiation with minimum volume expansion and imparting good conductivity and short diffusion length for Li+ ions. Electrochemical studies demonstrate that these 3D architectured electrodes are promising as efficient anodes for high‐performance lithium‐ion battery devices.

We report the fabrication of vertically aligned hierarchical arrays of TiO2/ZnO hybrid nanowires, consisting of ZnO nanowires grown directly from within the pores of TiO2 nanotubes, through a combination of electrochemical anodization and hydrothermal techniques. These novel nano-architectured hybrid nanowires with its unique properties show promise as high performance supercapacitor electrodes. The electrochemical behaviour of these hybrid nanowires has been studied using Cyclic voltammetry, Galvanostatic charge-discharge and Electrochemical impedance spectroscopy (EIS) measurements using 1.5 M tetraethylammoniumtetrafluoroborate in acetonitrile as the electrolyte. Excellent electrochemical performances with a maximum specific capacitance of 2.6 mF cm-2 at a current density of 10 µA cm-2, along with exceptional cyclic stability, have been obtained for TiO2/ZnO-1 h hybrid material. The obtained results demonstrate the possibility of fabricating new geometrical architectures of inorganic hybrid nanowires with well adhered interfaces for the development of hybrid energy devices.

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