Sodium-ion batteries (SIBs) have emerged as a promising alternative for grid-scale energy storage owing to their cost-effectiveness and the natural abundance of sodium resources. Coal-derived hard carbons present particularly attractive anode candidates, combining the advantages of abundant reserves, low cost, and high carbon yield. However, the inherent abundant aromatic structures of coal precursors often lead to excessive graphitization during thermal conversion, which degrades the sodium storage performance. Herein, we demonstrate a strategic heteroatom co-doping approach to modulate the microcrystalline structure of coal-derived hard carbons. By simultaneous incorporation of S and N atoms, this approach effectively suppresses graphitization while promoting the formation of electrochemically favorable pseudo-graphitic domains. The optimized S/N co-doped hard carbon (S/N-CHC-1) anode delivers exceptional electrochemical performance, including a high reversible capacity of 349.8 mAh g−1 and an initial Coulombic efficiency of 62.6% at 0.03 A g−1. Through comprehensive characterization, the dominant intercalation mechanism is elucidated in the low-voltage plateau region and clear structure-performance relationships are established. This work provides fundamental insights into heteroatom engineering for regulating hard carbon microcrystalline environments and offers a practical pathway for developing high-performance coal-derived hard carbon anodes for next-generation SIBs.

Sodium-ion batteries (SIBs) are emerging as a sustainable alternative to lithium-ion batteries for large-scale energy storage, but their development is hindered by the lack of cost-effective, high-performance anode materials. This study introduces an eco-friendly synthesis method for nitrogen/phosphorus (N/P) codoped hollow hard carbon microspheres derived from cornstarch, leveraging hydrothermal precarbonization with ammonium polyphosphate (APP) followed by high-temperature pyrolysis. The APP facilitates simultaneous N/P doping and gas evolution during pyrolysis to form hollow architectures. The combined effects of heteroatom doping and structural engineering significantly enhance ion transport kinetics and improve electrolyte accessibility, resulting in notably improved sodium-storage performances. The optimized hard carbon has a reversible capacity of 309.5 mAh g-1 at 0.03 Ag-1 and demonstrates excellent cycling stability with a capacity retention of 86.7% after 1000 cycles at 1 Ag-1. The improvements can be attributed to the heteroatom doping that induces a large interlayer spacing (0.392 nm), high defect content, and a substantial hierarchical porous surface area (415.88 m2/g), which collectively enhance conductivity and sodium-ion kinetics. This work not only advances the design of biomass-derived hard carbon anodes but also provides a scalable strategy for sustainable energy-storage materials.

Two-dimensional layered MoS2 has been considered the most promising anode material for potassium-ion batteries (PIBs) due to its relatively large interlayer spacing and high theoretical specific capacity. Despite extensive research on their electrochemical performance, reaction mechanisms, structural changes, and kinetic behavior during potassiation processes are still unknown or controversial. Here, in situ transmission electron microscopy was used to track the migration of potassium ions in the layered structure of MoS2 nanosheets in real time at the atomic scale. These results reveal that the potassiation process proceeds in a region-by-region manner, namely, a multistep intercalation reaction initiated from the outer region to the adjacent inner region. Meanwhile, the local stress induced by the insertion of potassium ions results in structural distortion, deformation, and dislocation formation. Additionally, the potassiation behaviors of MoS2 nanosheets only involve intercalation, and the final product is identified as KxMoS2, which is quite different from the mechanisms of lithiation and sodiation. Meanwhile, density functional theory calculations verified that less electrovalent K-S bonds inhibit the occurrence of the conversion reaction, favoring maintenance of the MoS2 layered structure. This work provides valuable insights into the potassiation mechanisms of MoS2 and guides the design of high-performance anodes for PIBs.

In NiP-based catalysts, although Ni2 P and Ni5 P4 have relatively high catalytic activity, the catalytic performance of single-phase Ni2 P or Ni5 P4 is still far from that of noble metal catalysts. The dual-phase heterojunction has better catalytic performance than single-phase materials due to its faster interface charge transfer rate and more active sites. The Ni2 P/Ni5 P4 @CC heterostructural catalyst with oriented porous nanosheet arrays grown on carbon cloth (CC), was in-situ constructed through the controllable phase transition of Ni2 P. By modulating the amount of P source (P-dependent) or the phosphating reaction time (Time-dependent), the degree of the Ni2 P phase transition could be modulated, thus obtaining the Ni2 P/Ni5 P4 @CC heterostructural catalyst with the required component ratio of Ni2 P and Ni5 P4 . When the ratio of Ni2 P and Ni5 P4 was 15.7:84.3, the Ni2 P/Ni5 P4 @CC catalyst had the best catalytic performance. Its hydrogen evolution reaction (HER) overpotentials were only 139 and 87 mV overpotentials reaching -10 mA/cm2 in 1 mol/L KOH and 0.5 mol/L H2 SO4 , respectively, which was much lower than that of the single-phase Ni2 P@CC (base: 278 mV; acid: 123 mV) and Ni5 P4 @CC (base: 166 mV; acid: 106 mV) catalysts. Specially, in acidic electrolyte, HER overpotential at a higher current density of -100 mA/cm2 of the Ni2 P/Ni5 P4 @CC catalyst was 270 mV, which was even lower than that of the Pt/C catalyst (328 mV), indicating that the Ni2 P/Ni5 P4 @CC heterostructural catalysts had promising prospects for commercial applications. The mechanism of catalytic performance enhancement was investigated by the density functional theory (DFT) calculations. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

In NiP-based catalysts,although Ni2P and Ni5P4 have relatively high catalytic activity,the catalytic per-formance of single-phase Ni2P or Ni5P4 is still far from that of noble metal catalysts.The dual-phase heterojunction has better catalytic performance than single-phase materials due to its faster interface charge transfer rate and more active sites.The Ni2P/Ni5P4@CC heterostructural catalyst with oriented porous nanosheet arrays grown on carbon cloth(CC),was in-situ constructed through the controllable phase transition of Ni2P.By modulating the amount of P source(P-dependent)or the phosphating reac-tion time(Time-dependent),the degree of the Ni2P phase transition could be modulated,thus obtaining the Ni2P/Ni5P4@CC heterostructural catalyst with the required component ratio of Ni2P and Ni5P4.When the ratio of Ni2P and Ni5P4 was 15.7∶84.3,the Ni2P/Ni5P4@CC catalyst had the best catalytic performance.Its hydrogen evolution reaction(HER)overpotentials were only 139 and 87 mV overpotentials reaching-10 mA/cm2 in 1 mol/L KOH and 0.5 mol/L H2SO4,respectively,which was much lower than that of the single-phase Ni2P@CC(base:278 mV;acid:123 mV)and Ni5P4@CC(base:166 mV;acid:106 mV)cata-lysts.Specially,in acidic electrolyte,HER overpotential at a higher current density of-100 mA/cm2 of the Ni2P/Ni5P4@CC catalyst was 270 mV,which was even lower than that of the Pt/C catalyst(328 mV),indi-cating that the Ni2P/Ni5P4@CC heterostructural catalysts had promising prospects for commercial applica-tions.The mechanism of catalytic performance enhancement was investigated by the density functional theory(DFT)calculations.

Lithium-sulfur (Li-S) batteries are regarded as promising next-generation energy-storage systems owing to their high theoretical energy density and low cost. However, their practical application is hindered by several challenges, including the polysulfide shuttle effect, poor conductivity of sulfur species, and sluggish redox kinetics. To address these issues, we designed and synthesized a heterostructure composed of Fe3O4/FeS2 encapsulated in nitrogen-doped carbon shells (Fe3O4/FeS2-CS), which serves as a multifunctional catalyst for separator modification and sulfur host. The core-shell architecture synergistically combines the strong polysulfide-adsorption capability of Fe3O4 with the efficient catalytic-conversion property of FeS2, while the outer carbon shell provides physical confinement of polysulfides and enhances electrical conductivity. When coated on a polypropylene (PP) separator, the Li-S cell exhibits a low capacity-decay rate of only 0.057% per cycle over 500 cycles at 1 C. Under a high sulfur loading of 6.6 mg cm-2, the cell retains 91.1% of its capacity after 100 cycles. Moreover, the dry-processed Fe3O4/FeS2-CS/S cathode achieves a sulfur loading as high as 10.2 mg cm-2, delivering an initial discharge capacity of 1058 mAh g-1 at 0.05 C under lean-electrolyte conditions, with 92% capacity retention after 50 cycles. This work presents a well-structured strategy to integrate adsorption and catalysis within a heterostructure catalyst, offering a promising route toward high-performance and practical Li-S batteries.

MnO2-based zinc-ion batteries (ZIBs) are an energy storage system characterized by high-safety, low cost, and high theoretical capacity. However, MnO2 cathodes suffer from poor conductivity and structural instability, which are detrimental to their energy storage performance. Herein, we utilize a carbon nanotube-pitch-derived porous carbon (CNT-PPC) sponge as a self-supporting substrate for depositing MnO2. As a ZIB cathode, the CNT-PPC-MnO2 sponge exhibits a high specific capacity of 411.7mAh/g at 0.1A/g, high rate capability, and stable cycling performance. The zinc-ion storage kinetics are investigated via electrochemical mechanism analysis and calculations. The as-prepared CNT-PPC-MnO2 sponge//Zn ZIB can deliver a high-energy density of 556Wh/kg. This work provides a design strategy of a self-supporting carbon-based substrate for loading active materials.

Hard carbon derived from coal is a promising anode material for sodium-ion batteries (SIBs), yet its performance is often limited by irreversible capacity loss and poor rate capability. Herein, we report a synergistic modification strategy for coal-based hard carbon involving S/N co-doping and a conformal soft carbon coating. S/N co-doping expands carbon interlayer spacing and introduces electroactive sites, while soft carbon coating effectively passivates surface defects, increases the closed-pore volume, and modulates the interfacial properties. Consequently, the S/N-CHC@SC delivers a reversible capacity of 360.1 mAh g−1 with an enhanced initial Coulombic efficiency of 74.58% at 0.03 A g−1 with 63.1% of this capacity contributed by the low-voltage plateau region. It also demonstrates excellent rate capability and remarkable cycling stability (94.9% capacity retention after 100 cycles at 0.03 A g−1). Mechanistic studies identify a sodium storage mechanism involving synergistic adsorption, intercalation and pore filling processes. This work provides a practical and effective approach designing high-performance coal-based hard carbon anodes for advanced SIBs, promoting the value-added utilization of coal in energy storage systems.

Metal halide perovskite nanocrystals (NCs) are promising luminescent materials for optoelectronic applications. However, the highly sensitive nature of the perovskite lattice to water significantly limits the perovskite NCs for photocatalysis in aqueous phase. Here, we present a core-shell engineering strategy based on an epoxide-mediated sol-gel process to grow metal oxides on the surfaces of perovskite NCs. Benefit from the versatile inorganic metal salts, different metal oxides (such as SnO2, Al2O3, and Eu2O3) are deposited onto the perovskite core under ambient conditions. Owing to the protection of dense metal oxide shell, the exemplified SnO2@CsPbBr3 NCs display intense emission after annealing and slightly photoluminescence (PL) quenching in water over 30 days. Interestingly, they additionally behave outstanding dispersibility in water (with a zeta potential of ∼42 mV). These features, combined with the type II band alignment of SnO2@CsPbBr3 NCs facilitating the photo-generated charge separation, result in a NH4 + production rate of 47 µmol g-1·h-1 without any sacrificial agents. This work explores a generalized approach to produce core-shell structured perovskite NCs to enhance their aqueous stability. Besides, it also expands the aqueous applications of perovskite communities and gives a guideline for designing novel nitrogen fixation photocatalysts.

The vast compositional space of high-entropy materials makes the discovery of superior solid electrolytes extremely challenging. Here, we introduce a hybrid artificial intelligence (AI) framework that synergistically combines unsupervised learning with crystal graph convolutional neural networks (CGCNN) in a dual-stage screening architecture. This approach navigates >1800 potential Zr-site doped Li7La3Zr2O12 (LLZO) compositions, first partitioning them into 21 distinct groups via unsupervised clustering, then focusing on a high-potential group (G19) for precise CGCNN prediction of band gaps and Li+ diffusion barriers. This AI-identified optimal high-entropy electrolyte, Li7La3Zr0.4Cr0.4Mo0.4Sn0.4Ta0.4O12 (HE-LLZO), would otherwise require years of trial-and-error. Entropy stabilization lowers the synthesis temperature to 920 °C and suppresses detrimental Li2CO3/LiOH surface formation. Bond valence site energy (BVSE) calculations, supported by solid-state NMR and geometric phase analysis, reveal that the high-entropy configuration introduces moderate lattice distortion (dσ = 0.104 Å) and significantly flattens the 3D Li+ migration energy landscape, reducing the macroscopic diffusion barrier from 1.060 eV (pristine LLZO) to 0.777 eV. Consequently, HE-LLZO achieves a high ionic conductivity of 1.05 × 10−3 S cm−1, a low activation energy of 0.287 eV, and an expanded electrochemical window of 4.81 V. All-solid-state cells with Ta-doped NCM811 cathodes retain 92.5% capacity after 250 cycles, and flexible pouch cells (NCM90|SE|Li-alloy) deliver 200.1 mAh g−1 with 86% retention after 200 cycles, demonstrating practical viability. This work establishes a generalizable, AI-guided paradigm for accelerating the discovery of high-entropy solid electrolyte toward high-energy-density batteries.

Hard carbon (HC) stands out as a promising anode material for sodium-ion batteries (SIBs) due to its abundance, low cost, and excellent safety. However, its widespread application is hindered by limited reversible capacity and sluggish kinetics, which originate from the suboptimal microstructure. Here, we develop a synergistic nitrogen and phosphorus codoped strategy to modulate the microstructure of biomass-derived hard carbon. Using coconut shells as a sustainable carbon source and diammonium hydrogen phosphate as a dual-functional dopant, a series of N/P codoped hard carbon (PNHC-x) are synthesized via a facile two-step carbonization process. The introduction of N/P heteroatoms collaboratively expands the interlayer spacing, enhances local graphitic ordering, and constructs a hierarchical porous architecture with a high specific surface area. When evaluated as an SIB anode, the optimized PNHC-1 delivers a high reversible capacity of 311.1 mA h & centerdot;g-1 with an initial Coulombic efficiency of 67.95%, a superior plateau capacity of 194.25 mA h & centerdot;g-1. Furthermore, it demonstrates outstanding long-term cyclability, retaining a capacity of 58.34 mA h & centerdot;g-1 after 1000 cycles at 1 A & centerdot;g-1 with 113.7% capacity retention. Kinetics analyses confirm that the N/P codoping strategy significantly reduces charge-transfer resistance and accelerates Na+ diffusion. This work provides a green, template-free synthesis route using agricultural waste, positioning this strategy as a practical and sustainable approach for high-performance SIB anodes.

Traditional von Neumann architecture-based devices are limited by the memory wall, hindering the development of next-generation artificial intelligence. Controlling proton transport to achieve hydrogenation in monolayer graphene resulting in the reversible and controllable nature of their memristive behavior has attracted significant interest for neuromorphic applications. However, multilayer graphene is impermeable to protons and most ions, which severely restricts the development of graphene-based neuromorphic devices in practice. To address this challenge, we developed a three-terminal artificial synapse based on stacked graphene nanosheets induced by an organic nano carbon source (ONCS). The device achieves co-regulated proton transport and hydrogenation through the gate-source voltage (VGS) and source-drain voltage (VDS), enabling dual-stimulus memristive effects (gate stimulus and source-drain stimulus). It successfully mimics essential synaptic functions, including short-term depression (STD), long-term depression (LTD), and paired-pulse depression (PPD) with intensity-dependent and pulse number-sensitive responses. This work resolves the ion-electron co-regulation challenge in multilayer graphene for next-generation AI computing.

The development of composite solid electrolytes with high ionic conductivity and superior interfacial stability is crucial for practical all-solid-state lithium metal batteries (ASSLMBs). Herein, a high-performance bilayer composite separator is designed by integrating Li0.33La0.557TiO3 (LLTO) nanofibers into a poly(vinylidene fluoride) (PVDF) matrix, which is coated onto a polyethylene (PE) substrate. The interconnected LLTO nanofibers construct three-dimensional continuous ion-conducting pathways and reduce the crystallinity of the polymer matrix, endowing the optimized separator (with 60 wt % LLTO) with a high ionic conductivity of 5.17 & times; 10-4 S cm-1, a large lithium-ion transference number (tLi += 0.81), and a wide electrochemical stability window up to 4.87 V. The unique bilayer architecture, where the LLTO/PVDF layer facilitates rapid Li+ transport and the PE layer ensures interfacial compatibility, enables stable lithium plating/stripping over 500 h and yields a high critical current density of 2.9 mA cm-2. Furthermore, the robust mechanical properties of the separator ensure uniform lithium-ion flux and effectively resist lithium dendrite penetration. When applied in NCM811/Li metal battery, this modified solid-state electrolyte separator enabled remarkable cycling stability (89.8% capacity retention after 200 cycles at 5C) and exceptional rate performance (115.4 mAh g-1 at 5C). This work provides a feasible and effective strategy for designing composite separators toward high-energy-density and dendrite-free ASSLMBs.

Large-ion (K, Na) battery systems mitigate uneven global lithium distribution, while their ability to attain recharge time shorter than refueling would remove the final barrier for secondary batteries to replace petroleum vehicles. However, their large-ion chemistry makes ultra-fast charging an even significant challenge. Controlling and designing the stacking of chemically modified graphene nanosheets (GNS) to tailor multi-dimensional structures offers great potential in this aspect, which is attributed to the large interlayer distance and topological geometry structure for shortening the ion and electron transfer path and strengthening the absorption of ions. Conventional synthesis methods are confined to pristine 2D sublattices, lacking uniform molecular structures and clear self-assembly mechanisms. Herein, a triple-nanoparticles (Tri-NPs) system is proposed to obtain multi-dimensional, well-defined, and accurately stacked GNS structures, including 3D GNS-sieves, 2D GNS-holey nanosheets, and 1D GNS-hollow spheres. Consequently, the 1D GNS-hollow spheres demonstrate a recharging time comparable to refueling petroleum-powered vehicles-merely 3.76 min over 1250 cycles at 15.96 C in potassium-ion batteries (PIBs) and 3.36 min over 3000 cycles at 17.86 C in sodium-ion batteries (SIBs). This opens new perspectives for addressing the long-standing criticism of electric vehicles over prolonged charging times through the development of battery systems featuring high-rate charge-discharge performance and low-cost materials.

Solid-state lithium metal batteries hold great potential for next-generation energy storage, yet their performance is often limited by the ionic conductivity and interfacial stability of solid electrolytes. Herein, we develop a lowtemperature sintering strategy to fabricate a chloride-based solid electrolyte, Li0.388Ta0.238La0.475Cl3 (LLTC), featuring a unique amorphous-crystalline dual-phase structure. Through precise control of sintering temperature (250-450 degrees C), we modulate the vacancy concentration and crystallinity of LLTC, achieving an optimal ionic conductivity of 1.26 mS cm- 1 at 20 degrees C and an ultra-low activation energy of 0.14 eV. Comprehensive analysis and DFT results indicate that the amorphization significantly reduces Li+ binding energy and enhances the ionic conductivity, while the retained crystalline framework ensures high oxidation stability up to 4.88 V. Furthermore, the optimized LLTC was incorporated into a polyvinylidene fluoride (PVDF) matrix to form a flexible composite electrolyte membrane. When assembled into solid-state batteries, the LiFePO4||PVDF/LLTC||Li cell exhibits excellent cycling stability, retaining 96.2% of its initial capacity after 600 cycles at 1C. Coupled with a high-voltage LiNi0.8Co0.1Mn0.1O2 cathode, the cell demonstrates stable operation for 100 cycles at a high rate of 5C. This work highlights the effectiveness of amorphous-crystalline phase engineering in chloride solid electrolytes, offering a promising route towards high-performance, durable solid-state lithium batteries.

Designing highly efficient nonprecious metal electrocatalyst for the hydrogen evolution reaction (HER) in seawater electrolyte, particularly under ultra-high current density conditions, remains a formidable challenge. In this study, we successfully synthesized a crystalline/amorphous heterostructured CoNi/MoO3-x electrocatalyst through a facile hydrothermal method followed by a calcination-reduction process. The as-prepared CoNi/MoO3- x catalyst exhibited remarkable HER catalytic performance in both alkaline water and seawater electrolytes. Notably, the catalyst achieved impressively low overpotentials of 343 mV in 1 M KOH aqueous solution and 294 mV in alkaline natural seawater electrolyte at an ultra-high current density of 4000 mA/cm2. Furthermore, the CoNi/MoO3-x electrocatalyst demonstrated outstanding long-term stability, maintaining robust performance at current densities of 3000 and 2000 mA/cm2. Density functional theory calculations revealed that the synergetic effect between crystalline CoNi and amorphous MoO3-x accelerates water dissociation kinetics and optimizes hydrogen adsorption. These findings not only provide a promising strategy for developing cost-effective, non- precious metal electrocatalysts with superior HER performance at ampere-level current densities, particularly for seawater splitting applications.

Lithium-sulfur (Li-S) batteries are poised to become the next-generation energy storage technology due to their ultra-high energy density of 2600 Wh kg- 1 and the abundant reserves of sulfur on Earth. However, the practical use of Li-S batteries faces several challenges related to sulfur cathodes, including low sulfur loading, significant volumetric expansion, slow conversion kinetics, and the shuttle effect caused by polysulfides. To tackle these challenges, we have developed a hierarchical porous carbon co-doped with nitrogen, oxygen, and sulfur heteroatoms (NOSHPC) that is further loaded with monodispersed vanadium nitride quantum dots (VNQDs). This innovative combination serves as an efficient catalytic matrix to enhance charge transfer processes and facilitate the anchoring and conversion of lithium polysulfides. Moreover, we have fabricated dry-processed cathodes with ultrahigh sulfur loading by using fibrotic polytetrafluoroethylene (PTFE) as a binder, replacing the toxic solvent N-methyl-2-pyrrolidone and polyvinylidene fluoride. The dry-processed VNQDs/NOSHPC/S cathodes demonstrate a remarkable specific capacity of 1655mAh g- 1 at 0.1C and achieve exceptional cycling stability, with a decay rate of only 0.0107 % per cycle over 1000 cycles at 1C with a sulfur loading of 5.2 mg cm- 2. Additionally, the pouch cells containing these dry-processed electrodes exhibit a practical areal capacity of 14.2mAh cm- 2 (462 Wh kg- 1) with a sulfur loading of up to 18.6 mg cm- 2 and a low electrolyte-to-sulfur ratio of 5.3 mu L mg- 1. This work presents an innovative strategy for creating sulfur hosts and practical dry-processed Li-S electrodes, highlighting promising prospects for industrial application.

Solid-state lithium metal batteries (SSLMBs) face critical challenges from dendrite growth and unstable interfaces. While composite polymer electrolytes (CPEs) offer promise, poor ionic conductivity (<10(-5) S cm(-1)), low Li+ transference numbers (t(Li+) < 0.5), and inadequate interfacial stability limit practical application. Herein, we design a dual-channel metal-organic framework (MOF)-based CPEs that simultaneously regulate ion transport and construct a high-conductivity interphase. This MOF features two distinct channels. The one imposes spatial confinement (0.57 nm in pore size) to suppress anion migration (TFSI-), while the other facilitates immobilizing TFSI- through iodine-mediated nucleophilic substitution. More importantly, the liberated I- reacts with Li+ to in situ generate lithium iodide (LiI)-enhanced solid-electrolyte interphase (SEI), replacing insulating LiF-rich counterparts. This LiI-SEI exhibits superior ionic conductivity and homogenizes Li+ flux to suppress dendrites. Integrated into a poly(vinylidene fluoride)-cohexafluoropropylene (PVDF-HFP) matrix, the MOF CPE achieves exceptional ionic conductivity (2.13x10(-4) S cm(-1)) and a high t(Li+) of 0.95 (25 degrees C). Density functional theory and molecular dynamics calculations verify ion-regulation mechanisms. As a result, LiFePO4//Li cells retain 94.99% capacity after 800 cycles (1 C), while NCM811//Li cells demonstrate sustained stability over 200 cycles. This work provides valuable insights into the design of multifunctional MOF ionic conductors for high-performance SSLMBs. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

High-energy-density anode materials are crucial for achieving high performance alkali metal-ion batteries (AMIBs). In situ transmission electron microscopy (TEM) enables real-time observation of microstructural changes in electrode materials and interfaces during charging/discharging, crucial for designing high-performance anodes. This paper highlights and reviews the dynamic studies of the relationship between the structure and the electrochemical performance of carbon-based composite materials used as anodes in AMIBs by in situ TEM. First, the in situ TEM technique and cell construction method are introduced, followed by an overview of in situ TEM integrates with other advanced measurement techniques. Second, the fundamental working principles of various AMIBs and the energy storage mechanisms of anode materials are explained, along with the achievable functions of in situ TEM in AMIBs. Third, from different carbon matrix structures, including carbon-supported, carbon-embedded, carbon-coated, carbon-encapsulated, and hybrid carbon-composite structures, in situ dynamic studies on the electrochemical behaviors of these carbon-based anode materials by TEM are covered in depth. Finally, a summary of the design ideas and the technical application of in situ TEM for carbon-based anode composites is provided, followed by a suggestion for current challenges and future research paths.

Lithium-sulfur batteries have high theoretical energy density while their practical application is trapped because of severe shuttle effect and sluggish conversion kinetics of polysulfides. Here, a nitrogen, oxygen, and sulfur codoped porous carbon (NOSAKC) is prepared by one-step pyrolysis of acesulfame potassium, which is employed as an efficient component on polypropylene separators to restrict the shuttle of polysulfides based on Lewis acidbase theory. The NOSAKC exhibits a hierarchical porous structure with high specific surface area and abundant adsorption/catalytic sites. The substantial mesoporous channels are conducive to rapid ion transfer, and the micropores minimize the polysulfide shuttle. The abundant heteroatoms doped in NOSAKC can achieve synergistic constraint and conversion of lithium polysulfides. So the Li-S battery with the NOSAKC separator displays distinguished electrochemical performance with a high discharge capacity of 1598 mAh g- 1 at 0.2 C and 1012 mAh g- 1 at 1 C. It maintains 84 % of the initial capacity after 500 cycles with a stable coulombic efficiency of 99.8 %. Moreover, the Li-S battery achieves a capacity retention of 67 % after 200 cycles for a high sulfur loading of 4.33 mg cm- 2. This work reports a one-step preparation of hierarchical porous carbon with tri-doped heteroatoms for synergistic polysulfide adsorption and conversion.