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The pursuit of advanced materials to meet the escalating demands of energy storage system has led to the emergence of vertical graphene (VG) as a highly promising candidate. With its remarkable strength, stability, and conductivity, VG has gained significant attention for its potential to revolutionize energy storage technologies. This comprehensive review delves deeply into the synthesis methods, structural modifications, and multifaceted applications of VG in the context of lithium–ion batteries, silicon-based lithium batteries, lithium–sulfur batteries, sodium–ion batteries, potassium–ion batteries, aqueous zinc batteries, and supercapacitors. The review elucidates the intricate growth process of VG and underscores the paramount importance of optimizing process parameters to tailor VG for specific applications. Subsequently, the pivotal role of VG in enhancing the performance of various energy storage and conversion systems is exhaustively discussed. Moreover, it delves into structural improvement, performance tuning, and mechanism analysis of VG composite materials in diverse energy storage systems. In summary, this review provides a comprehensive look at VG synthesis, modification, and its wide range of applications in energy storage. It emphasizes the potential of VG in addressing critical challenges and advancing sustainable, high-performance energy storage devices, providing valuable guidance for the development of future technologies. [ABSTRACT FROM AUTHOR]

Fe7S8 as a conversion‐type anode shows high capacity in lithium‐ion batteries (LIBs). Nevertheless, the sluggish ion transport rate, low electron conduction behavior, and large volume change upon cycling limit its applications in fast‐charging wide‐temperature‐range LIBs. Here, a simple hydrothermal and subsequent solid‐phase high‐pressure sulfidation route is proposed to synthesize a hollow Fe7S8/N‐doped C microsphere structure. The hollow space is enveloped by the spheres’ shell consisting of ultrafine Fe7S8 nanocrystals (≈8 nm) embedded into N‐doped C matrix, which enhances ion transport and electrical conduction, and accommodates the volume expansion of Fe7S8. Remarkably, in situ magnetometry reveals that spin‐polarized surface capacitance occurs during the stage of conversion reaction, in which the formed Fe and Li2S act as electrons and ions acceptor, respectively, to construct space charge zone at their interfaces, thus enhancing lithium transport and storage. Accordingly, the hollow microspheres show high gravimetric energy density and outstanding fast‐charging capability along with excellent cycling stability in Ah‐level pouch cells operating from ‐40 to 60 °C. For the first time, this work confirms the effectiveness of spin‐polarized surface capacitance effect on enhancing ion storage and transport in fast‐charging wide‐temperature‐range LIBs. [ABSTRACT FROM AUTHOR]

Electrodes, which offer sites for mass transfer and redox reactions, play a crucial role in determining the energy efficiencies and power densities of redox flow batteries. This review focuses on various approaches to enhancing electrode performance, particularly the methods of surface etching and catalyst deposition, as well as some other advanced strategies for regulating electrode surface properties. These approaches aim to increase active sites and enhance kinetics for the redox reactions, which are crucial for elevating power density and electrolyte utilization, eventually determining the performance of the flow battery. Highlighting the need for interdisciplinary research, this mini‐review suggests that future advancements in electrode design will significantly impact the commercial viability and adoption of redox flow batteries in sustainable energy storage solutions. [ABSTRACT FROM AUTHOR]

MoS2 is widely reported as anode material for sodium‐ion batteries (SIBs). However, its ability to operate effectively across a wide temperature range and at high rates continues to pose fundamental challenges, limiting its further development. Herein, a monolayer Fe‐doped MoS2/N,O‐codoped C overlapping structure is designed and employed as an anode for wide‐temperature‐range SIBs. Fe doping imparts MoS2 electrode with zero bandgap characteristics, an increased interlayer spacing, and low sodium‐ion diffusion energy barriers across wide operation temperatures. Impressively, Fe atoms doped into the MoS2 lattice can be reduced to superparamagnetic Fe0 nanocrystals of ≈2 nm during conversion reactions. In situ magnetometry reveals that these Fe0 nanocrystals can be used as electron acceptor in the formation of space charge zones with Na+, thereby triggering strong spin‐polarized surface capacitance that facilitates fast sodium‐ion storage over a wide temperature range. Consequently, the designed MoS2 electrode demonstrates exceptional fast‐charging capability in half/full cells operating at −40–60 °C. This study provides novel perspectives on the utilization of heteroatom doping strategies in conversion‐type electrode material design and proves the effectiveness of spin‐polarized surface capacitance effect on enhancing sodium‐ion storage over a wide temperature range. [ABSTRACT FROM AUTHOR]

The germanium (Ge) anode attains wide attention in lithium‐ion batteries because of its high theoretical volumetric capacity (8646 mAh cm−3). However, the huge volume expansion (≈230%) results in its poor electrochemical performances. The strategies reported in the literature to solve the issue often cause a low packing density, lowering the volumetric capacity. Here, a pressure‐induced route is proposed to fabricate a Ge architecture, in which nano‐sized Ge (≈15 nm) is encapsulated by robust TiO2 and highly conductive carbon, which offer the advantages of a low stress–strain characteristic, low volume expansion in thickness change, high electrical conductivity (463.2 S m−1), high Li‐ion diffusion coefficient (9.55 × 10−9–8.51 × 10−12 cm2 s−1), and high tapping density (1.79 g cm−3). As a result, the dense architecture obtains outstanding volumetric capacities of 3559.8 mAh cm−3 at 0.1 A g−1 and 2628.2 mAh cm−3 at 20 A g−1, along with excellent cycling life over 5000 cycles at 10 A g−1. Remarkably, the full cell achieves a high volumetric energy density of 1760.1 Wh L−1, along with impressive fast‐charging performances and long cycling life. This work provides a new synthesis strategy and deep insight into the design of high‐volumetric capacity alloy‐based lithium‐ion‐battery anodes. [ABSTRACT FROM AUTHOR]

Iron sulfide (FeS) has been extensively studied as sodium‐ion battery anodes due to its high theoretical capacity (609 mAh g−1), but its large volume expansion and low electrical conductivity result in unsatisfactory cycling life and poor rate performance. Moreover, the sodium ion storage mechanism of FeS at a voltage range of 0.01–1 V involving conversion reactions and subsequent ion storage process is unclear yet. Here, the study proposes a vapor‐pressure induced synthesis route to fabricate FeS/C yolk‐shell structure that ultrathin carbon layers coat on the surface of FeS nanosheets, which can accommodate volume expansion of FeS during sodiation observed via in situ transmission electron microscope and improve its electrical conductivity. Remarkably, an in situ magnetometry reveals that vast spin‐polarized electrons can be injected into superparamagnetic Fe nanoparticles (≈3 nm) formed during conversion reaction to induce evolution of electrode magnetization between 0.01 and 1 V, during which spin‐polarized surface capacitance effect occurs at Fe/Na2S interfaces to increase extra ion storage and boost ion transport stably. Consequently, the FeS/C yolk‐shell nanosheets deliver a high reversible capacity of 664.9 mAh g−1 at 0.1 A g−1, and 300.4 mAh g−1 after 10 000 cycles at 10 A g−1 with a capacity retention of 81.1%. [ABSTRACT FROM AUTHOR]

Silicon (Si) is widely used as a lithium‐ion‐battery anode owing to its high capacity and abundant crustal reserves. However, large volume change upon cycling and poor conductivity of Si cause rapid capacity decay and poor fast‐charging capability limiting its commercial applications. Here, we propose a multilevel carbon architecture with vertical graphene sheets (VGSs) grown on surfaces of subnanoscopically and homogeneously dispersed Si–C composite nanospheres, which are subsequently embedded into a carbon matrix (C/VGSs@Si–C). Subnanoscopic C in the Si–C nanospheres, VGSs, and carbon matrix form a three‐dimensional conductive and robust network, which significantly improves the conductivity and suppresses the volume expansion of Si, thereby boosting charge transport and improving electrode stability. The VGSs with vast exposed edges considerably increase the contact area with the carbon matrix and supply directional transport channels through the entire material, which boosts charge transport. The carbon matrix encapsulates VGSs@Si–C to decrease the specific surface area and increase tap density, thus yielding high first Coulombic efficiency and electrode compaction density. Consequently, C/VGSs@Si–C delivers excellent Li‐ion storage performances under industrial electrode conditions. In particular, the full cells show high energy densities of 603.5 Wh kg−1 and 1685.5 Wh L−1 at 0.1 C and maintain 80.7% of the energy density at 3 C. [ABSTRACT FROM AUTHOR]

Silicon (Si) anodes, known for their high capacity, confront obstacles such as volume expansion, the solid–electrolyte interface (SEI) formation, and limited cyclability, driving ongoing research for innovative solutions to enhance their performance in next‐generation lithium‐ion batteries (LIBs). This comprehensive review explores the forefront of one‐dimensional (1D) Si/carbon anodes for high‐performance LIBs. This review delves into cutting‐edge strategies for fabricating 1D Si/carbon structures, such as nanowires, nanotubes, and nanofibers, highlighting their advantages in mitigating volume expansion, enhancing electron/ion transport, and bolstering cycling stability. The review showcases remarkable achievements in 1D Si/carbon anode performance, including exceptional capacity retention, high‐rate capability, and prolonged cycle life. Challenges regarding scalability, cost‐effectiveness, and long‐term stability are addressed, providing insights into the path to commercialization. Additionally, future directions and potential breakthroughs are outlined, guiding researchers and industries toward harnessing the potential of 1D Si/carbon anodes in revolutionizing energy storage. [ABSTRACT FROM AUTHOR]

Fe3O4 is widely investigated as an anode for ambient sodium‐ion batteries (SIBs), but its electrochemical properties in the wide operation‐temperature range have rarely been studied. Herein, the Fe3O4 nanoparticles, which are well encapsulated by carbon nanolayers, are uniformly dispersed on the graphene basal plane (named Fe3O4/C@G) to be used as the anode for SIBs. The existence of graphene can reduce the size of Fe3O4/C nanoparticles from 150 to 80 nm and greatly boost charge transport capability of electrode, resulting in an obvious size decrease of superparamagnetic Fe nanoparticles generated from the conversion reaction from 5 to 2 nm. Importantly, the ultra‐small superparamagnetic Fe nanoparticles (≈2 nm) can induce a strong spin‐polarized surface capacitance effect at operating temperatures ranging from −40 to 60 °C, thus achieving highly efficient Na‐ion transport and storage in a wide operation‐temperature range. Consequently, the Fe3O4/C@G anode shows high capacity, excellent fast‐charging capability, and cycling stability ranging from −40 to 60 °C in half/full cells. This work demonstrates the viability of Fe3O4 as anode for wide operation‐temperature SIBs and reveals that spin‐polarized surface capacitance effects can promote Na‐ion storage over a wide operation temperature range. [ABSTRACT FROM AUTHOR]

The irreversible oxygen redox and structural degradation of LiNi0.8Co0.1Mn0.1O2 (NCM811) at a 4.5 V high voltage cause a severe decline in cycling performance for lithium‐ion batteries. In this study, a novel approach is proposed to enhance the anionic redox chemistry and stability of NCM811 cathode material by introducing gaseous selenium. Seβ+ species are selectively adsorbed within oxygen vacancies, leading to the continuous replacement of Oα− to form a stable O–TM–Se bond during deep charging. Furthermore, Selenium modification improves cationic redox efficiency and alleviates Oα− (α < 2) outward migration, increases oxygen vacancy formation energy. The redox activity of oxygen is diminished, facilitating improved reversibility of oxygen redox and effectively inhibiting irreversible oxygen escape. Additionally, Selenium increases the energy barrier for phase transition, effectively suppressing irreversible phase transition and Ni migration. Selenium reacts with escaping oxygen to form SeO2, effectively reducing side reactions during cycling. As a result, the proposed approach significantly inhibits irreversible oxygen release, leading to remarkable cyclic stability with 87.5% capacity retention after 300 cycles at 1C at 4.5 V and maintained 192.9 mAh g−1 after 150 cycles under 60C. The Se modification realizes stability anionic redox strategy to design novel high‐energy‐density cathode materials with superior cycling performance. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2), a typical two-dimensional transition metal dichalcogenides, is a promising candidate for electrochemical water splitting catalysis due to its ultrahigh special area and highly exposed active edge sites. The main challenges restricted the wider application for MoS2-based nanomaterials are the complex preparation process and the high overpotential. Here, we design a novel and facile sealed vessel to synthesize vertical oriented MoS2 nanosheets electrocatalyst with vast exposed edges. Benefiting from the unique vertically-oriented structural and compositional characteristics, the MoS2 nanosheets with 10-20 layers exhibits superior hydrogen evolution reaction (HER) performance with a small overpotential of 135.2 mV at a current density of 10 mA∙cm-2 and low Tafel slope of 82.5 mV∙dec-1 as well as extraordinary catalytic stability over 5000 cycles. Importantly, the sealed vessel reactor system may open up a versatile and potential synthetic way to construct various morphologies and structure of metal dichalcogenides for high-performance energy storage and conversions devices.

As high theoretical capacity and excellent electrical conductivity, Co9S8 as a promising electrode material in lithium-ion batteries (LIBs) has attracted wide attention. In the present work, a simple vaporpressured induced route is developed for fabricating spherical-like Co9S8/N, S-codoped carbon nanocomposites (Co9S8/NSC), in which Co9S8 nanoparticles with an average size of 100 nm are encapsulated into N, S-codoped carbon matrix, by pyrolysis of mixture of cobalt isooctanoate dissolved into dimethylformamide and thiourea in a sealed vessel for the first time. As anode for LIBs, the Co9S8/NSC shows an excellent reversible capacity, a superior rate performance, and a long cycling stability. For example, a high capacity of 975.3 mA h g-1 can be achieved after 100 cycles at 0.1 A g-1. When cycled at 1 A g-1, it also maintains a high specific capacity of 791.5 mA h g-1 after 1000 cycles. Besides, it also shows a superior rate performance (329.8 mAh g-1 at 20 A g-1). Such superior performances may arise from its structural advantages that the smaller Co9S8 nanoparticles encapsulated into N, S-codoped carbon could enhance active sites, electrical conductivity, and structural stability.

Single‐layered MoS2 is a promising anode material for lithium‐ion batteries (LIBs), sodium‐ion batteries (SIBs), and potassium‐ion batteries (PIBs) due to its high capacity and isotropic ion transport paths. However, the low intrinsic conductivity and easy‐agglomerated feature hamper its applications. Here, a charge‐driven interlayer expansion strategy that Co2+ replaces Mo4+ in the doping form to endow MoS2 layers with negative charges, thus inducing electrostatic repulsion, together with the insertion of gaseous groups, to drive interlayer expansion which once breaks the confinement of interlayer van der Waals force, single‐layered MoS2 is obtained and uniformly dispersed into carbon matrix arising from the transformation of carbonaceous gaseous groups under high vapor pressure, is proposed. Co atom doping helps enhance the intrinsic conductivity of single‐layered MoS2. Carbon matrix effectively prevents agglomeration of single‐layered MoS2. The doped Co atoms can be fully transformed into ultrasmall Co nanoparticles during conversion reaction, which enables strong spin‐polarized surface capacitance and thus significantly boosts ion transport and storage. Consequently, the prepared material delivers superb Li/Na/K‐ion storage performances, which are best in the reported MoS2‐based anodes. The proposed charge‐driven interlayer expansion strategy provides a novel perspective for preparing single‐layered MoS2, which shows huge potential for energy storage. [ABSTRACT FROM AUTHOR]