The limited potassium‐ion intercalation capacity of graphite hampers development of potassium‐ion batteries (PIB). Edge‐nitrogen doping is an effective approach to enhance K‐ion storage in carbonaceous materials. One shortcoming is the lack of precise control over producing the edge‐nitrogen configuration. Here, a molecular‐scale copolymer pyrolysis strategy is used to precisely control edge‐nitrogen doping in carbonaceous materials. This process results in defect‐rich, edge‐nitrogen doped carbons (ENDC) with a high nitrogen‐doping level (up to 10.5 at %) and a high edge‐nitrogen ratio (87.6 %). The optimized ENDC exhibits a high reversible capacity of 423 mAh g−1, a high initial Coulombic efficiency of 65 %, superior rate capability, and long cycle life (93.8 % retention after three months). This strategy can be extended to design other edge‐heteroatom‐rich carbons through pyrolysis of copolymers for efficient storage of various mobile ions.

Conventional graphite anodes can hardly intercalate sodium (Na) ions, which poses a serious challenge for developing Na‐ion batteries. This study details a novel method that involves single‐step laser‐based transformation of urea‐containing polyimide into an expanded 3D graphene anode, with simultaneous doping of high concentrations of nitrogen (≈13 at%). The versatile nature of this laser‐scribing approach enables direct bonding of the 3D graphene anode to the current collectors without the need for binders or conductive additives, which presents a clear advantage over chemical or hydrothermal methods. It is shown that these conductive and expanded 3D graphene structures perform exceptionally well as anodes for Na‐ion batteries. Specifically, an initial coulombic efficiency (CE) up to 74% is achieved, which exceeds that of most reported carbonaceous anodes, such as hard carbon and soft carbon. In addition, Na‐ion capacity up to 425 mAh g−1 at 0.1 A g−1 has been achieved with excellent rate capabilities. Further, a capacity of 148 mAh g−1 at a current density of 10 A g−1 is obtained with excellent cycling stability, opening a new direction for the fabrication of 3D graphene anodes directly on current collectors for metal ion battery anodes as well as other potential applications.

The limited potassium‐ion intercalation capacity of graphite hampers development of potassium‐ion batteries (PIB). Edge‐nitrogen doping is an effective approach to enhance K‐ion storage in carbonaceous materials. One shortcoming is the lack of precise control over producing the edge‐nitrogen configuration. Here, a molecular‐scale copolymer pyrolysis strategy is used to precisely control edge‐nitrogen doping in carbonaceous materials. This process results in defect‐rich, edge‐nitrogen doped carbons (ENDC) with a high nitrogen‐doping level (up to 10.5 at %) and a high edge‐nitrogen ratio (87.6 %). The optimized ENDC exhibits a high reversible capacity of 423 mAh g−1, a high initial Coulombic efficiency of 65 %, superior rate capability, and long cycle life (93.8 % retention after three months). This strategy can be extended to design other edge‐heteroatom‐rich carbons through pyrolysis of copolymers for efficient storage of various mobile ions.

Lithium-sulfur (Li-S) battery is a promising next-generation rechargeable battery with high energy density. Given the outstanding capacities of sulfur (1675 mAh g −1 ) and lithium metal (3861 mAh g −1 ), Li-S battery theoretically delivers an ultra-high energy density of 2567 Wh kg −1 . However, this energy density cannot be realized due to several factors, particularly the shuttling of polysulfide intermediates between the cathode and anode, which causes serious degradation of capacity and cycling stability of a Li-S battery. In this work, a simple and scalable route was employed to construct a free-standing laser scribed graphene (LSG) interlayer which effectively suppresses the polysulfide shuttling in Li-S batteries. Thus, a high specific capacity (1160 mAh g -1 ) with excellent cycling stability (80.4% capacity retention after 100 cycles) has been achieved due to the unique structure of hierarchical three-dimensional pores in the free-standing LSG.

Sulfur‐based batteries are regarded as potent candidates for next‐generation high‐energy and low‐cost energy storage systems. However, sulfur‐based batteries still face substantial obstacles on the cathode side (e.g., low conductivity and sluggish reaction kinetics of sulfur) and the anode side (e.g., dendrite growth), severely hindering their utilization. MXenes (i.e., 2D transition metal carbides, nitrides, and carbonitrides), as an emerging member of the 2D material family, possess unique electrochemical and electronic properties, which make them attractive materials to enhance the performance of sulfur‐based batteries. In this article, a comprehensive review of the research progress on using MXenes in sulfur‐based batteries is provided. The basics of MXene and sulfur‐based batteries are introduced first, wherein the merits of applying MXenes in sulfur‐based batteries are discussed. Subsequently, the progress in this field is systematically summarized in terms of the roles of MXene in sulfur‐based batteries, including MXene as sulfur host, MXene‐based composite as sulfur host, MXene‐based separator modification, and MXene‐based advanced electrodes. In the end, recommendations for specific future research directions to advance the development of MXenes for sulfur‐based batteries are outlined.