The introduction of high-entropy into Prussian blue analogues (PBAs) has yet to attract attention in the field of lithium-sulfur battery materials. Herein, we systematically synthesize a library of PBAs from binary to high-entropy by a facile coprecipitation method. The coordination environment in PBAs is explored by X-ray absorption fine structure spectroscopy, which together with elemental mapping confirm the successful introduction of all metals. Importantly, electrochemical tests demonstrate that high-entropy PBA can serve as polysulfide immobilizer to inhibit shuttle effect and as catalyst to promote polysulfides conversion, thereby boosting its outstanding performance. Additionally, a variety of nanocubic metal oxides from binary to senary are fabricated by using PBAs as sacrificial precursors. We believe that a wide range of new materials obtained from our coprecipitation and pyrolysis methodology can promote further developments in research on PBA systems and sulfur hosts.

SnSx (x = 1, 2) compounds are composed of earth‐abundant elements and are nontoxic and low‐cost materials that have received increasing attention as energy materials over the past decades, owing to their huge potential in batteries. Generally, SnSx materials have excellent chemical stability and high theoretical capacity and reversibility due to their unique 2D‐layered structure and semiconductor properties. As a promising matrix material for storing different alkali metal ions through alloying/dealloying reactions, SnSx compounds have broad electrochemical prospects in batteries. Herein, the structural properties of SnSx materials and their advantages as electrode materials are discussed. Furthermore, detailed accounts of various synthesis methods and applications of SnSx materials in lithium‐ion batteries, sodium‐ion batteries, and other new rechargeable batteries are emphasized. Ultimately, the challenges and opportunities for future research on SnSx compounds are discussed based on the available academic knowledge, including recent scientific advances.

Metal‐organic frameworks (MOFs) have emerged as a promising material with unique features such as diverse composition, high porosity, tunable pore structure, and versatile functionality. These characteristics have attracted significant research interest in photochemical and electrochemical energy conversion and storage (ECS). However, the utilization of pristine MOFs in ECS is still hindered by their limited conductivity and functionality. Recently, the integration of MOFs with functional materials has been studied intensively to surmount the deficiencies of pristine MOFs while maintaining their original advantages. The MOFs act as the essential active species, or as supports to accommodate and stabilize these materials. The incorporation can deliver synergistic effects and enhance the properties of MOFs, thus greatly improving their efficiency and stability in ECS. The favorable nanostructures of MOF composites with different dimensionalities including 0D, 1D, 2D, and 3D can further enrich their structural diversity. Their advanced nanostructures contribute greatly to the enhanced structural robustness, exposure of active sites, and mass/electron transport, which are promising for practical ECS. In this review, recent progress in the rational design of MOF composites with different dimensionalities is summarized. The extensive applications of MOF composites for ECS systems are also discussed for elucidating their advantages, challenges, and prospects.

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Framework materials, such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), offer huge potential for applications in many aspects due to their well‐defined topologies, high crystallinity, inherent porosity, and chemical tunability. One advanced concept of further functionalizing the single framework materials is to construct hybrid frameworks (e.g., MOF‐on‐MOF, MOF‐on‐COF, and COF‐on‐MOF). Herein, different MOF‐based hybrid frameworks with complex compositions and well‐designed structures show excellent properties that cannot be achieved by single framework materials. The synthetic approaches of MOF‐based hybrid frameworks and their related applications are summarized. The opportunities and challenges for MOF‐based hybrid frameworks are also discussed.