Developing hybrid metal−organic frameworks (MOFs) with ordered structure is significant to obtain promising electrode materials for supercapacitors. Herein, the special electrodes of CuCo 2 O 4 /NiCo-MOF nanoflake vertical arrays are constructed on Ni foam by using the CuCo 2 O 4 nanorods as a selfsacrifice template. Because of the multidirectional interconnected channels of spinel CuCo 2 O 4 , great electrochemical activity of NiCo-MOF, well-arranged morphology, and synergy effect at the interface, the resulting CuCo 2 O 4 /NiCo-MOF nanoflakes exhibit remarkable specific capacity (12.81 F/cm 2 or 1423 F/g at 2 mA/ cm 2 ) and excellent rate performance (remaining 79.2% at 30 mA/ cm 2 ). The asymmetric supercapacitor assembled by CuCo 2 O 4 / NiCo-MOF and an activated carbon electrode shows excellent energy density of 0.48 mWh/cm 2 at a power density of 1.50 mW/cm 2 . This work inspires insight into exploiting hybrid MOFs with highly aligned arrays for energy storage.

A high-quality and centimeter-level three-dimensional (3D) nitrogen-doped graphene (NG) nanonetwork is synthesized via a chemical vapor deposition method to serve as a substrate and a current collector, which directly germinates active metal oxides to act as a free-standing electrode in lithium-ion batteries. By means of facile electrodeposition and annealing processes, the tetragonal spinel cobalt–manganese oxide nanosheets wrapped with polypyrrole pyrolytic carbon are in situ hybridized with a 3D NG nanonetwork. In particular, the introduced carbon protective layer can enhance the Li-ion storage capacity and cycle stability of the composite electrode. The metallic synergistic effect and rational carbonaceous hybridization jointly provide high-performance charge storage and cycle stability. Notably, the surface-controlled capacitive effect stands out contributing to the total charge storage more than ever in nanostructure electrodes.

The hierarchically porous iron phosphide nanospindles with nitrogen–phosphorus-codoped carbon coatings (FeP@NPC) are fabricated via a combination of hydrothermal synthesis and subsequent phosphating treatment, which is extensively researched for elevating the outstanding performance of lithium-ion batteries (LIBs). The as-prepared FeP@NPC nanocomposite manifests a distinguished specific capacity of 1100 mA h g–1 after 200 cycles at 0.2 A g–1, a ranking rate performance with a high capacity of ∼600 mA h g–1 at 5 A g–1, and a reversible long cycling capacity of 951.7 mA h g–1 after 800 cycles at 1 A g–1. The superior properties can be ascribed to the joint contribution of the well-designed porous nanostructure and conductive N, P-codoped carbon coating, which simultaneously facilitates efficient transmission of lithium ions and electrons, contributes to mild volume expansion, and elevates structural stability during the reversible charge–discharge process.

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The two-dimensional layered material tin disulfide (SnS 2 ) has a high theoretical capacity for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to its combination of conversion and alloying reactions during the charge-storage process. However, the intrinsic poor conductivity and huge volume changes impede its practical applications. In this work, a design of in situ growth and polymerization is developed to synthesize polypyrrole wrapped SnS 2 vertical nanosheet arrays grown on nitrogen-doped three-dimensional graphene (PPy@SnS 2 @N3DG). The PPy@SnS 2 @ N3DG composite, with the unique free-standing hierarchical structure and the synergy of three components, exhibits excellent rate capability and superior cycling stability. Based on the features of high capacity, lightweight, and facile preparation, the PPy@SnS 2 @ N3DG composite can be considered as a promising electrode for energy storage devices.