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Rational designing and constructing multiphase hybrid electrode materials is an effective method to compensate for the performance defects of the single component. Based on this strategy, Cu2Se hexagonal nanosheets@Co3Se4 nanospheres mixed structures have been fabricated by a facile two‐step hydrothermal method. Under the synergistic effect of the high ionic conductivity of Cu2Se and the remarkable cycling stability of Co3Se4, Cu2Se@Co3Se4 can exhibit outstanding electrochemical performance as a novel electrode material. The as‐prepared Cu2Se@Co3Se4 electrode displays high specific capacitance of 1005 F g−1 at 1 A g−1 with enhanced rate capability (56 % capacitance retention at 10 A g−1), and ultralong lifespan (94.2 % after 10 000 cycles at 20 A g−1). An asymmetric supercapacitor is assembled applying the Cu2Se@Co3Se4 as anode and graphene as cathode, which delivers a wide work potential window of 1.6 V, high energy density (30.9 Wh kg−1 at 0.74 kW kg−1), high power density (21.0 Wh kg−1 at 7.50 kW kg−1), and excellent cycling stability (85.8 % after 10 000 cycles at 10 A g−1).

Rational construction of heterostructures can compensate for the property shortfalls of a single component, which is a promising and challenging approach to develop high‐performance electrode materials. Herein, CuCo carbonate hydroxide nanowires@FeCo‐layered double hydroxide hexagonal nanosheets (CuCo‐CH@FeCo‐LDH) with a unique nanowire‐penetrated‐nanosheet architecture have been prepared through a facile two‐step hydrothermal method. The nanowires serve as fast channels for charge transfer of FeCo‐LDH and alleviate the blocked electroactive utilization induced by self‐stacking of LDH nanosheets, while the FeCo‐LDH contributes high specific capacitance. The resultant CuCo‐CH@FeCo‐LDH exhibits pseudocapacitive behavior with near‐rectangular CV profiles and overall enhanced electrochemical performance compared to individual CuCo‐CH and FeCo‐LDH. An assembled asymmetric supercapacitor (CuCo‐CH@FeCo‐LDH//N/S co‐doped graphene) delivers high energy density (46.9 Wh kg−1 at 750 W kg−1), high power density (29.0 Wh kg−1 at 7500 W kg−1), and outstanding cycling stability (81.7 % capacitance retention after 5000 cycles).

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