Dual-MnCo2O4/Ni electrode with three-level hierarchy for high-performance electrochemical energy storage

The design of micro/nanostructures with high porosity is very important to achieve reliable and high-performance capacitive materials for electrochemical energy storage. The complexity of this strategy is limited by the lack of a facile method to synthesize multi-hierarchical architectures with both high electroactive surface area and fast ion diffusion ability. Here, we report a designed MnCo2O4/Ni electrode with multilevel hierarchy containing mesoporous MnCo2O4 nanosheet layers and vertically aligned MnCo2O4 nanoflake layers on a macroporous Ni foam support (∼500 μm). The dual-MnCo2O4 layers are well connected with each other and grown directly on the Ni foam support. As a result, the obtained dual-MnCo2O4/Ni electrode delivers an excellent specific capacity up to 283 mAh g−1 and long-term performance stability over 2000 cycles.