Superlattices are rising stars on the horizon of energy storage and conversion, bringing new functionalities; however, their complex synthesis limits their large‐scale production and application. Herein, a simple solution‐based method is reported to produce organic–inorganic superlattices and demonstrate that the pyrolysis of the organic compound enables tuning their interlayer space. This strategy is exemplified here by combining polyvinyl pyrrolidone (PVP) with WSe2 within PVP/WSe2 superlattices. The annealing of such heterostructures results in N‐doped graphene/WSe2 (NG/WSe2) superlattices with a continuously adjustable interlayer space in the range from 10.4 to 21 Å. Such NG/WSe2 superlattices show a metallic electronic character with outstanding electrical conductivities. Both experimental results and theoretical calculations further demonstrate that these superlattices are excellent sulfur hosts at the cathode of lithium–sulfur batteries (LSB), being able to effectively reduce the lithium polysulfide shuttle effect by dual‐adsorption sites and accelerating the sluggish Li–S reaction kinetics. Consequently, S@NG/WSe2 electrodes enable LSBs characterized by high sulfur usages, superior rate performance, and outstanding cycling stability, even at high sulfur loadings, lean electrolyte conditions, and at the pouch cell level. Overall, this work not only establishes a cost‐effective strategy to produce artificial superlattice materials but also pioneers their application in the field of LSBs.

Developing high-performance cathode host materials is fundamental to solve the low utilization of sulfur, the sluggish redox kinetics, and the lithium polysulfide (LiPS) shuttle effect in lithium–sulfur batteries (LSBs). Here, a multifunctional Ag/VN@Co/NCNT nanocomposite with multiple adsorption and catalytic sites within hierarchical nanoreactors is reported as a robust sulfur host for LSB cathodes. In this hierarchical nanoreactor, heterostructured Ag/VN nanorods serve as a highly conductive backbone structure and provide internal catalytic and adsorption sites for LiPS conversion. Interconnected nitrogen-doped carbon nanotubes (NCNTs), in situ grown from the Ag/VN surface, greatly improve the overall specific surface area for sulfur dispersion and accommodate volume changes in the reaction process. Owing to their high LiPS adsorption ability, outer Co nanoparticles at the top of the NCNTs catch escaped LiPS, thus effectively suppressing the shuttle effect and enhancing kinetics. Benefiting from the multiple adsorption and catalytic sites of the developed hierarchical nanoreactors, Ag/VN@Co/NCNTs@S cathodes display outstanding electrochemical performances, including a superior rate performance of 609.7 mAh g–1 at 4 C and a good stability with a capacity decay of 0.018% per cycle after 2000 cycles at 2 C. These properties demonstrate the exceptional potential of Ag/VN@Co/NCNTs@S nanocomposites and approach LSBs closer to their real-world application.

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One-dimensional bunched nanostructures have attracted particular research interest for their applications in energy-relate fields. However, developing a reasonable strategy to realize such unique structure design still remains a great challenge. Herein, we first rationally design and synthesize a distinct one-dimensional bunched Ni–MoO2@Co–CoO–NC composite through an efficient strategy of assembling the metal–organic framework (MOF) and transition metal oxide (TMO), in which the MOF-derived Co–CoO–NC polyhedra are stringed by the Ni–MoO2 nanowires. The synthesis strategy only involves the effective integration of the ZIF-67 polyhedron with NiMoO4·xH2O nanowires via solution growth at room temperature followed by a carbonation treatment under an Ar/H2 atmosphere. Benefiting from the favorable morphological and structural merits as well as the synergistic effects from different components, the bunched Ni–MoO2@Co–CoO–NC composite exhibits a remarkable half-battery performance when evaluated as the anode material for both lithium/sodium-ion batteries. Furthermore, electrode kinetic analyses reveal the capacitive-controlled behaviors within the bunched Ni–MoO2@Co–CoO–NC composite. Besides, a Ni–MoO2@Co–CoO–NC//LiFePO4 full cell is fabricated, which can deliver a high energy density of 329 Wh kg–1. The present study could provide an insight into the construction of TMOs and carbon composites with one-dimensional bunched nanostructures.

Searching for high-performance Ni-based cathodes plays an important role in developing better aqueous nickel–zinc (Ni–Zn) batteries. For this purpose, herein, we demonstrate the design and synthesis of ultrathin α-Ni­(OH)2 nanosheets branched onto metal–organic frameworks (MOFs)-derived 3D cross-linked N-doped carbon nanotubes encapsulated with tiny Co nanoparticles (denoted as Co@NCNTs/α-Ni­(OH)2), which are directly supported on a flexible carbon cloth (CC). An aqueous Ni–Zn battery employing the hierarchical CC/Co@NCNTs/α-Ni­(OH)2 as the binder-free cathode and a commercial Zn plate as the anode is fabricated, which displays an ultrahigh capacity (316 mAh g–1) and energy density (540.4 Wh kg–1) at 1 A g–1 as well as excellent rate capability (238 mAh g–1 at 10 A g–1) and superior cycling performance (about 84% capacity retention after 2000 cycles at 10 A g–1). The impressive electrochemical performance might benefit from the rich active sites, rapid electron transfer, cushy electrolyte access, rapid ion transport, and robust structural stability. In addition, the quasi-solid-state CC/Co@NCNTs/α-Ni­(OH)2//Zn batteries are also successfully assembled with polymer electrolyte, indicating the great potential for portable and wearable electronics. This work might provide important guidance for constructing carbon-based hybrid materials directly supported on conductive substrates as high-performance electrodes for energy-related devices.

Lithium–sulfur (Li–S) batteries hold great promise for the next‐generation energy storage system. However, their commercial applications are severely hindered by myriads of drawbacks such as poor electrical conductivity of sulfur, sluggish redox reaction kinetics of sulfur species, “shuttling effect” of soluble lithium polysulfides (LiPSs) and uncontrollable dendritic Li growth. Herein, it is conceptually demonstrated that sluggish conversion kinetics of LiPSs is markedly stimulated by exquisite heterointerface modulation at nanoscale level over transition metal carbides and nitrides. In this scenario, N‐doped carbon coupled with molybdenum nitride/carbide (Mo2N‐MoC/NC) hybrid nanocomposites are designed through a one‐step carbonization‐nitridation process, wherein component regulation induced dense heterointerfaces are in situ produced. Benefiting from high electrical conductivity, strong chemical adsorption, and superior catalytic activity afforded by dense heterointerfaces, the Mo2N‐MoC/NC modified separators significantly restrict the soluble LiPSs shuttling and simultaneously suppress the Li dendrite generation. The assembled Li–S batteries with Mo2N‐MoC/NC modified separators exhibit remarkable electrochemical performance. Integrated experimental and theoretical results substantiate the boosted chemisorption and catalytic conversion of LiPSs endowed by such dense heterointerfaces. The work will open a new vista for rationally constructing multifarious heterostructured materials for the communities of Li‐S batteries.

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