Synthesis and performances of a ZnCo 2 O 4 @MnMoO 4 composite for a hybrid supercapacitor.

To overcome the disadvantages of poor intrinsic conductivity and stability of ZnCo 2 O 4 , a ZnCo 2 O 4 @MnMoO 4 composite as an emerging pseudocapacitor electrode material with high specific capacitance, environmental friendliness, morphological diversity, and unique hierarchical structure was synthesized via a simple two-step hydrothermal method. The research results indicate that the ZnCo 2 O 4 @MnMoO 4 composite can present a high specific capacity of 1628 F g -1 at a current density of 1 A g -1 and good cycling stability with 69% capacity retention after 10 000 cycles at 10 A g -1 . Hybrid supercapacitors (HSCs) assembled with the ZnCo 2 O 4 @MnMoO 4 cathode and activated carbon anode can deliver an energy density of 48 W h kg -1 at a power density of 695 W kg -1 , and their capacity retention reached 61% after 8000 charge-discharge cycles at a current density of 10 A g -1 . This could be attributed to the synergistic effect of the specific surface area and electrical conductivity enhanced by compositing ZnCo 2 O 4 with MnMoO 4 . As a result, the excellent electrochemical properties show that the ZnCo 2 O 4 @MnMoO 4 composite has strong application potential for high-performance supercapacitors.