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• Ni(Co)MoO 4 hybrid electrode with a mixed structure was synthesized on nickel foam. • The hybrid electrode exhibits a remarkable cycling performance due to the mixed morphology. • The asymmetric supercapacitor shows a high energy density of 55.71 Wh kg−1 at the power density of 375 W kg−1. [Display omitted] In this work, the Ni(Co)MoO 4 (NMO-Co) hybrid materials with nanoneedle and nanosheet structure were prepared on nickel foam (NF) by the hydrothermal method for high-stability supercapacitors. The effect of Co presence on the structure and electrochemical properties of NMO-Co was investigated. As the molar of Cobalt increased, more nanoneedles grew on the surface of NiMoO 4 /NF. The combination of the Ni-doped CoMoO 4 nanoneedles and Co-doped NiMoO 4 nanosheets was irregularly arranged on the surface of NF, which emerged an improvement of the cycling performance. When the molar ratio of Co: Ni: Mo was 0.5: 1: 1, the capacitance retention of the hybrid electrode was 80.1% after 10,000 cycles at 10 A g−1, while the pure NiMoO 4 electrode was 53.1%. Moreover, an asymmetric supercapacitor device displayed high energy density and power density. The maximum energy density and power density could reach 55.71 Wh kg−1 and 14,999 W kg−1, respectively. The hybrid electrode's good electrochemical performance is due to the combination of mutual doping of Ni and Co with a mixed morphology. [ABSTRACT FROM AUTHOR]

• NF/ZnCo 2 O 4 @NiCo 2 O 4 heterostructures electrodes are fabricated via facile two-step methods. • The impact of all components in integrated electrode was investigated and discussed. • The integrated electrode exhibits excellent specific capacitance and cycling stability. • The hybrid supercapacitor delivers high energy and power densities. [Display omitted] The hierarchical core-shell heterostructures ZnCo 2 O 4 @NiCo 2 O 4 on Ni foam (NF) for supercapacitors were prepared via two-step hydrothermal and electrodeposition reactions followed by two post-annealing treatments. The effect of deposition time on its morphology and electrochemical performance was investigated in detail. Combining high electric conductivity of ZnCo 2 O 4 with high stability of NiCo 2 O 4 as well as synergistic effect, the NF/ZnCo 2 O 4 @NiCo 2 O 4 -100 (NF/ZCO@NCO-100) integrated electrode exhibited high specific capacitance of 1728.1 F g−1 (240.0 mAh g−1) at 1 A g−1, and excellent long-term stability with 97.8% capacitance retention after 10,000 cycles. The assembled hybrid supercapacitor (HSC) delivered the specific capacitance of 133.6 F g−1 (55.7 mAh g−1) at 1 A g−1 and high energy density of 40.58 Wh kg−1 at 745.62 W kg−1 as well as the outstanding long-term stability of 91.3% capacitance retention after 10,000 cycles. These results provide insights into the rational design of transition metal compound composite materials to construct integrated electrodes for high performance supercapacitors. [ABSTRACT FROM AUTHOR]