Construction of vertically aligned Ni-Co-Mo hybrid oxides nanosheet array for high-performance hybrid supercapacitors

Abstract

Multi-metal oxide materials have gained increasing attention due to their superior electrochemical performance for supercapacitors. In this work, Ni-Co-Mo oxides composite materials (NiCoMo/NF) are synthesized and anchored on Ni foam in the form of vertically aligned nanosheet arrays using a two-step hydrothermal method. It has confirmed that good electrochemical performance stems from a synergic interaction effect between the hybrid Ni-Co-Mo composite materials and the co-existence of Ni-Co and Co-Mo oxide, which can be attributed to a unique nanostructure in the hybrid Ni-Co-Mo composite materials and Ni-Co/Co-Mo oxide intersections with each other. The NiCoMo/NF binder-free electrode shows an enhanced specific capacitance of 1837.7 F g−1(3.31 F cm−2) at a current density of 1 A g−1 and maintains capacitance retention of 81.2% after 6000 cycles at 5 A g−1. Meanwhile, the fabricated hybrid capacitor achieves high specific energy of 41.1 W h kg−1. The results indicate that NiCoMo/NF has the potential for application in supercapacitors. Moreover, our work provides a practical approach for fabrication of multi-metal oxide materials and hold promise for high-power energy storage devices.