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Zinc ion batteries (ZIBs) have been gradually developed in recent years due to their abundant resources, low cost, and environmental friendliness. Therefore, ZIBs have received a great deal of attention from researchers, which are considered as the next generation of portable energy storage systems. However, poor overall performance of ZIBs restricts their development, which is attributed to zinc dendrites and a series of side reactions. Constructing 3D zinc anodes has proven to be an effective way to significantly improve their electrochemical performance. In this review, the challenges of zinc anodes in ZIBs, including zinc dendrites, hydrogen evolution and corrosion, as well as passivation, are comprehensively summarized and the energy storage mechanisms of the zinc anodes and 3D zinc anodes are discussed. 3D zinc anodes with different structures including fiberous, porous, ridge‐like structures, plated zinc anodes on different substrates and other 3D zinc anodes, are subsequently discussed in detail. Finally, emerging opportunities and perspectives on the material design of 3D zinc anodes are highlighted and challenges that need to be solved in future practical applications are discussed, hopefully illuminating the way forward for the development of ZIBs.

Engineering heterogeneous composite electrodes consisting of multiple active components for meeting various electrochemical and structural demands have proven indispensable for significantly boosting the performance of lithium‐ion batteries (LIBs). Here, a novel design of ZnS/Sn heterostructures with rich phase boundaries concurrently encapsulated into hierarchical interconnected porous nitrogen‐doped carbon frameworks (ZnS/Sn@NPC) working as superior anode for LIBs, is showcased. These ZnS/Sn@NPC heterostructures with abundant heterointerfaces, a unique interconnected porous architecture, as well as a highly conductive N‐doped C matrix can provide plentiful Li+‐storage active sites, facilitate charge transfer, and reinforce the structural stability. Accordingly, the as‐fabricated ZnS/Sn@NPC anode for LIBs has achieved a high reversible capacity (769 mAh g−1, 150 cycles at 0.1 A g−1), high‐rate capability and long cycling stability (600 cycles, 645.3 mAh g−1 at 1 A g−1, 92.3% capacity retention). By integrating in situ/ex situ microscopic and spectroscopic characterizations with theoretical simulations, a multiscale and in‐depth fundamental understanding of underlying reaction mechanisms and origins of enhanced performance of ZnS/Sn@NPC is explicitly elucidated. Furthermore, a full cell assembled with prelithiated ZnS/Sn@NPC anode and LiFePO4 cathode displays superior rate and cycling performance. This work highlights the significance of chemical heterointerface engineering in rationally designing high‐performance electrodes for LIBs.

Developing high-performance bifunctional electrocatalysts towards hydrogen evolution/oxidation reaction (HER/HOR) holds great significance for efficiently utilizing hydrogen energy. In this work, a unique class of Mo-modified Ru nanosheet assemblies (Mo-Ru NSAs)...

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Silicon (Si)‐based solid‐state batteries (Si‐SSBs) are attracting tremendous attention because of their high energy density and unprecedented safety, making them become promising candidates for next‐generation energy storage systems. Nevertheless, the commercialization of Si‐SSBs is significantly impeded by enormous challenges including large volume variation, severe interfacial problems, elusive fundamental mechanisms, and unsatisfied electrochemical performance. Besides, some unknown electrochemical processes in Si‐based anode, solid‐state electrolytes (SSEs), and Si‐based anode/SSE interfaces are still needed to be explored, while an in‐depth understanding of solid–solid interfacial chemistry is insufficient in Si‐SSBs. This review aims to summarize the current scientific and technological advances and insights into tackling challenges to promote the deployment of Si‐SSBs. First, the differences between various conventional liquid electrolyte‐dominated Si‐based lithium‐ion batteries (LIBs) with Si‐SSBs are discussed. Subsequently, the interfacial mechanical contact model, chemical reaction properties, and charge transfer kinetics (mechanical–chemical kinetics) between Si‐based anode and three different SSEs (inorganic (oxides) SSEs, organic–inorganic composite SSEs, and inorganic (sulfides) SSEs) are systemically reviewed, respectively. Moreover, the progress for promising inorganic (sulfides) SSE‐based Si‐SSBs on the aspects of electrode constitution, three‐dimensional structured electrodes, and external stack pressure is highlighted, respectively. Finally, future research directions and prospects in the development of Si‐SSBs are proposed.

Potassium‐ion batteries (PIBs) are considered promising alternatives to lithium‐ion batteries owing to cost‐effective potassium resources and a suitable redox potential of −2.93 V (vs. −3.04 V for Li+/Li). However, the exploration of appropriate electrode materials with the correct size for reversibly accommodating large K+ ions presents a significant challenge. In addition, the reaction mechanisms and origins of enhanced performance remain elusive. Here, tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs, and their live and atomic‐scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high‐resolution transmission electron microscopy. We found that FeSe undergoes two distinct structural evolutions, sequentially characterized by intercalation and conversion reactions, and the initial intercalation behavior is size‐dependent. Apparent expansion induced by the intercalation of K+ ions is observed in small‐sized FeSe nanoflakes, whereas unexpected cracks are formed along the direction of ionic diffusion in large‐sized nanoflakes. The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite‐element analysis. Despite the different intercalation behaviors, the formed products of Fe and K2Se after full potassiation can be converted back into the original FeSe phase upon depotassiation. In particular, small‐sized nanoflakes exhibit better cycling performance with well‐maintained structural integrity. This article presents the first successful demonstration of atomic‐scale visualization that can reveal size‐dependent potassiation dynamics. Moreover, it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs.

Constructing 3D skeletons modified with lithiophilic seeds has proven effective in achieving dendrite-free lithium metal anodes. However, these lithiophilic seeds are mostly alloy-or conversion-type materials, and they tend to aggregate and redistribute during cycling, resulting in the failure of regulating Li deposition. Herein, we address this crucial but long-neglected issue by using intercalation-type lithiophilic seeds, which enable antiaggregation owing to their negligible volume expansion and high electrochemical stability against Li. To exemplify this, a 3D carbon-based host is built, in which ultrafine TiO 2 seeds are uniformly embedded in nitrogendoped hollow porous carbon spheres (N-HPCSs). The TiO 2 @N-HPCSs electrode exhibits superior Coulombic efficiency, high-rate capability, and long-term stability when evaluated as compertitive anodes for Li metal batteries. Furthermore, the superiority of intercalation-type seeds is comprehensively revealed through controlled experiments by various in situ/ex situ electron and optical microscopies, which highlights the excellent structural stability and lithiophilicity of TiO 2 nanoseeds upon repeated cycling.