Development of energy storage systems with high energy, power density and long cycle life is very essential, as the global energy demand continues to grow with the growing dependence on portable electronic devices, electrically driven vehicles and smart grids. Hybrid capacitors that combine the advantages of both intercalation of cations (faradaic) and adsorption of anions (double layer) in the anode and cathode part from electrolytes, provides high energy and power density, respectively.[1,2] Recently sodium based devices are encouraged globally due to the dwindling of lithium resources. Na-ion hybrid capacitor emerged as a vital energy storage device and there is huge interest in designing efficient novel Na-insertion electrode material as the anode. Here we present the hydrothermally synthesised flower shaped layered sodium titanium oxide hydroxide [Na2Ti2O4(OH)2] as anode material, exhibits pseudocapacitive nature with a specific capacity of 150 mAh g-1 at 100 mA g-1 with good electrochemical kinetics showing a capacitive behaviour of 57.2% to the total capacity (323.3 C g-1), at 1.0 mV s-1, while the rest is due to Na-intercalation. Also conducted the diffusion coefficient studies of Na-ions inside the anode material by using GITT and EIS methods. Further, a full cell Na-ion capacitor is assembled with Na2Ti2O4(OH)2 as anode and chemically activated Rice Husk Derived Porous Carbon (RHDPC-KOH) as cathode, by using non-aqueous electrolyte (1 M NaPF6 in Propylene Carbonate). The device exhibits excellent electrochemical properties and delivers a remarkable energy density of ~65 Wh kg-1 with a maximum cell voltage of 4 V with more than ~ 93% capacitive retention after 3000 cycles.
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