Metal oxide nanostructures have been studied widely to overcome the limitations in the capacitance of the carbon-based supercapacitor electrode materials. An electrode with a very porous 3D structure is preferred to facilitate the mass transfer of large electrolyte ions. In this study, highly nanostructured, binder-free Ni-Co-based pseudocapacitive electrodes were synthesized directly on porous 3D structured nickel foam (NF) current collectors using low-power microwave irradiation. The electrochemical performance of the Ni-Co layered double hydroxide (Ni-Co-LDH) showed better performance than Ni-Co oxide (Ni-Co-O) with the further addition of redox additive/active electrolytes, such as K3Fe(CN)(6). The specific capacitances of 4664 F g(-1) for Ni-Co-LDH and 1.758 F g(-1) for Ni-Co-O at 5 mA cm(-2) in the KOHL K3Fe(CN)(6) electrolyte were improved greatly compared to the values of their corresponding materials in the conventional KOH electrolyte (2875 and 250 F g(-1), respectively). Interestingly, the Ni-Co-LDH//AC asymmetric device exhibited a specific capacitance of 108.9 F g(-1) and an energy density of 38.7 Wh kg(-1) with a stability of 61.9% after 5000 cycles. The facile yet cost-effective synthesis of nanostructured electrodes provides a versatile approach for the design of high-performance pseudocapacitive electrodes for future energy-storage systems. (C) 2017 Published by Elsevier Ltd.