Rational design and construction of nickel molybdate nanohybrid composite for high-performance supercapattery

Abstract Transition metal molybdates have attracted considerable devotion as a promising electrode material for energy storage devices owing to their enriched redox activity, good electronic conductivity, and stable crystal structure. Herein, we prepared the nickel molybdate (NiMoO4) nanohybrid composite on nickel (Ni) foam using a one-step hydrothermal method without using binders. The synthesized NiMoO4 material exhibited intertwined nanoflowers deposited nanosheets (NiMoO4 NFs@NSs). The high surface area of NFs and hierarchically connected NSs with open-porous voids and compact binding of nanohybrid morphology with Ni foam improve the electrochemical performance of the prepared material. Utilizing the morphological and active material features, the NiMoO4 NFs@NSs/Ni foam electrode exhibited a maximum specific capacity of 216 mA h/g (1989 F/g) at 3 mA/cm2. In addition, the prepared electrode demonstrated excellent cycling stability without fading even after long-term cycling. Furthermore, the supercapattery device was assembled with NiMoO4 NFs@NSs/Ni foam as a positive electrode and activated carbon as a negative electrode to investigate the practical applicability of the positive electrode. The fabricated supercapattery exhibited good energy storage performance, including a high specific capacitance of 38.6 F/g along with maximum energy and power densities of 13.2 W h/kg and 1644 W/kg, respectively. The potency of supercapattery in real-time feasibility was explored by operating different electronic components.