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Three‐dimensional asymmetric supercapacitors (3D ASC) have garnered significant attention due to their high operating window, theoretical energy density, and circularity. However, the practical application of 3D electrode materials is limited by brittleness and excessive dead volume. Therefore, we propose a controlled contraction strategy that regulates the pore structure of 3D electrode materials, eliminates dead volume in the 3D skeleton structure, and enhances mechanical strength. In this study to obtain reduced graphene oxide/manganese dioxide (rGO/MnO2) and reduced graphene oxide/carbon nanotube (rGO/CNT) composite aerogels with a stable and compact structure. MnO2 and CNT as nanogaskets, preventing the self‐stacking of graphene nanosheets during the shrinkage process. Additionally, the high specific capacitor nanogaskets significantly enhance the specific energy density of the rGO aerogel electrode. The prepared rGO/MnO2//rGO/CNT 3D ASC exhibits a high mass‐specific capacitance of 216.15 F g−1, a high mass energy density of 74 Wh kg−1 at 3.5 A g−1, and maintains a retention rate of capacitance at 99.89 % after undergoing 10,000 cycles of charge and discharge at 5 A g−1. The versatile and integrated assembly of 3D ASC units is achieved through the utilization of the robust mechanical structure of rGO‐based aerogel electrodes, employing a mortise and tenon structural design. [ABSTRACT FROM AUTHOR]

Nowadays, the development of advanced anode materials is highly desirable for the increasing demand for high‐performance lithium‐ion batteries (LIBs). Nanostructured MnO2 has received utmost attention due to high theoretical capacity (1230 mA h g−1), abundant resources, environmental benignity, and shortened electron and ion diffusion paths. Unfortunately, poor electronic conductivity and strong aggregation inclination of MnO2 nanostructures result in disappointing electrochemical performances, which restrict their practical application as sole institute. Here, we propose smartly designed MnO2@Fe3O4/CNT hybrid films, in which MnO2 nanosheets, Fe3O4 nanoparticles and CNTs are hierarchically assembled in a unique stage of nanosheets–nanoparticles–nanotubes. The resulting MnO2@Fe3O4/CNT hybrid films can be directly used as anodes without any polymer binders, and exhibit significant synergistic interactions among three components, achieving excellent reversible capacity and rate performance. Elegant! MnO2@Fe3O4/CNT hybrid films are smartly designed, in which MnO2 nanosheets, Fe3O4 nanoparticles and CNTs are hierarchically assembled in a unique stage of nanosheets–nanoparticles–nanotubes. The resulting binder‐free hybrid films achieve significant synergistic interactions among three components for superior lithium storage. [ABSTRACT FROM AUTHOR]

h-BN, as an isoelectronic analogue of graphene, has improved thermal mechanical properties. Moreover, the liquid-phase production of h-BN is greener since harmful oxidants/reductants are unnecessary. Here we report a novel hybrid architecture by employing h-BN nanosheets as 2D substrates to load 0D Fe3O4 nanoparticles, followed by phenol/formol carbonization to form a carbon coating. The resulting carbon-encapsulated h-BN@Fe3O4 hybrid architecture exhibits synergistic interactions: 1) The h-BN nanosheets act as flexible 2D substrates to accommodate the volume change of the Fe3O4 nanoparticles; 2) The Fe3O4 nanoparticles serve as active materials to contribute to a high specific capacity; and 3) The carbon coating not only protects the hybrid architecture from deformation but also keeps the whole electrode highly conductive. The synergistic interactions translate into significantly enhanced electrochemical performances, laying a basis for the development of superior hybrid anode materials. [ABSTRACT FROM AUTHOR]

We report a novel strategy for the hierarchical assembly of Ag nanoparticles (NPs) on MoS2 nanosheets through coordination by using a multifunctional organic ligand. The presence of Ag NPs on the surface of MoS2 nanosheets inhibits their agglomeration, thereby providing increased interlayer spacing for easy Li+ ion intercalation. Such a unique hybrid architecture also ensures sufficient percolation pathways on the whole surface of the MoS2 nanosheets. Moreover, the high rigidity and low deformability of the Ag NPs effectively preserve the hybrid architecture during the charge-discharge process, which translates into a high cycle stability. A prominent synergistic effect between MoS2 and Ag is witnessed. When the Ag content is only 5 wt %, the Ag-MoS2 hybrid delivers a reversible capacity as high as 920 mA h g−1 at a current density of 100 mA g−1, making the Ag-MoS2 hybrid an attractive candidate for next-generation LIBs. [ABSTRACT FROM AUTHOR]