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Chemical manipulation of surface functional groups on two‐dimensional transition metal carbides and/or nitrides (MXenes) provides a wide range of design and application prospects. However, achieving rapid targeted modification of surface groups remains a significant challenge. Herein, we propose a general strategy to swiftly shear and customize surface groups on Ti3C2Tx−MXene via the flash Joule heating (FJH) reaction within 1 s. Successfully, MXenes with 9 target terminations, including VII A (F, Cl, Br, or I), VI A (O, S, or Se), and V A (N or P), either single or multiple, are synthesized, with a surface content of up to about 76 %. The impact of these terminations is systematically analyzed on electrochemical performance, demonstrating that VI A and V A terminations have higher electrochemical activity than VII A. Particularly, N‐, S‐, and O‐terminated MXenes exhibit enhanced specific capacities and undecayed cycling performance. These findings offer valuable insights for the surface engineering design and performance optimization of functional materials. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) hold significant promise for large‐scale energy storage. While considerable strides have been made in modifying separators, the challenge of developing dendrite‐free, corrosion‐resistant, and cost‐effective separators for achieving extended cycling performance of Zn anodes persists. In light of this, a TiO2 coating separator to mitigate interfacial corrosion and passivation reactions, thereby facilitating high‐performance ZIBs is designed. This study delves into the influence of the loading amount and crystal phase of the TiO2 coating layers on separator modification. Zn symmetric cells employing the anatase TiO2‐modified glass fiber (A‐TiO2@GF) separator demonstrate superior Zn2+ ion transport kinetics in a mild ZnSO4 electrolyte, ensuring sustained long‐term stability and uniform Zn deposition. Furthermore, the reduced hydrogen evolution reaction (HER) activity of A‐TiO2 coatings curbs H+ ion migration, minimizing interfacial corrosion and HER. Consequently, the assembled Zn||CaV8O20 zinc‐ion full cells demonstrate outstanding long‐term durability and impressive specific capacity, boasting a discharge capacity of 142 mAh g−1 after 1000 cycles. This work introduces a straightforward interface engineering strategy for creating efficient separators in zinc‐ion batteries, promoting uniform Zn deposition. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) have stimulated extensive attention due to their environmental friendliness and low cost. Unfortunately, the inevitable dendrite growth and corrosion on the zinc (Zn) anode severely hinder the practical application of AZIBs. Herein, an amino acid containing an imidazole group is introduced as an effective additive to address these issues. The dynamic conversion of amino acid and protonated amino acid creates a pH buffer function that regulates solution pH in real time, inhibits hydrogen evolution reaction (HER), and eliminates notorious by‐products. In addition, the protonated amino acid is preferentially adsorbed on the Zn anode, preventing contact of the active water with the Zn surface and promoting homogeneous Zn deposition. Thus, the amino acid‐based electrolyte promotes dendrite free plating/stripping with a Coulombic efficiency up to 99.67% and cycle lifetime of 2600 h. In particular, a depth of discharge of up to 87% can be achieved with an ultra‐high areal capacity of 24 mAh cm−2. The developed Zn||CVO full cell also exhibits better electrochemical performance than that without additives. This work provides an effective and convenient approach for safe and efficient Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

The lack of high‐performance electrodes is a key factor restricting the development of sodium‐ion batteries (SIBs), and usually a certain type of electrode material alone often fails to combine the merits of high capacity and good conductivity. Herein, nitrogen‐doped carbon (NC) was used as a multifunctional bridge to uniformly compound high‐capacity MoS2 nanoparticles with highly conductive Ti3C2Tx nanosheets to form Ti3C2Tx@MoS2/NC composite with flower‐like architecture. Ultrafine MoS2 nanoparticles were uniformly anchored on Ti3C2Tx nanosheets to form nanosheets primary building blocks with a sandwich‐like architecture, which not only shortens the ion transfer distance but also enlarges the layer spacing of Ti3C2Tx favoring the storage of more sodium ions as well as their transport capacity. Moreover, the flower‐like structures with abundant edges can provide an ample active sites and high pseudocapacitance behavior. As a result, flower‐like Ti3C2Tx@MoS2/NC displays a high electrochemical properties with an excellent cycling stability over 2000 cycles (81.4 % capacity retention) and preeminent rate capacity of 383 mAh g−1 at 30 A g−1. Furthermore, Ti3C2Tx@MoS2/NC‖Na3V2(PO4)3 full cell displays a capacity of 59 mAh g−1 at 0.4 A g−1 after 180 cycles. This work displays a high‐performance anode composite for SIBs and provides insight into the preparation of other composites. [ABSTRACT FROM AUTHOR]

As post‐lithium ion batteries, both sodium‐ion batteries (SIBs) and potassium ion batteries (PIBs) possess great potential for large scale energy storage. However, the application of both SIBs and PIBs are hindered by the lack of suitable electrode materials. Here, we synthesized the sulfur decorated Ti3C2Tx (S−T3C2Tx) MXene as electrode material for SIBs and PIBs. Thanks to the sulfur functional group and the formation of Ti−S bond, which facilitates the sodium in‐/desertion and strengthens the potassium ion adsorption ability, as well as enhances ion reaction kinetics and improved structure stability, the S−T3C2Tx exhibit excellent sodium/potassium storage performance, high reversible capacities of 151 and 101 mAh g−1 at 0.1 mA g−1 were achieved for SIBs and PIBs, respectively. Moreover, the S−T3C2Tx exhibits remarkable long‐term capacity stability at a high density of 500 mA g−1, providing an impressive storage of 88 mAh g−1 for SIBs and 41 mAh g−1 for PIBs even after 2000 cycles. This work could give a deep comprehension of the heteroatom modification influence on the MXene‐based framework and promote the application of MXene electrodes. [ABSTRACT FROM AUTHOR]

Organic polymers have been considered reliable candidates for lithium storage due to their high capacity and lack of volume expansion. Compared with other organic polymers, polyimide has become a very promising electrode material for lithium‐ion batteries (LIBs) because of its easy synthesis, customizable structure and structural stability. A large number of studies have confirmed that the benzene ring structure of polyimide has strong lithium storage capacity as an anode material. Hence, we designed and synthesized polyimide organic polymer (PBPAQ) for the first time. The unique spherical flower structure of this material enhances the interaction between the electrode material and the electrolyte by increasing the contact area. The PBPAQ anode has a specific discharge capacity of 738 mAh g−1 after 100 cycles at 0.1 A g−1. The excellent lithium storage performance of this material laid a foundation for the research of the anode of LIBs in the future. [ABSTRACT FROM AUTHOR]

Binders play a critical role in rechargeable lithium‐ion batteries (LIBs) by holding granular electrode materials, conductive carbons, and current collectors firmly together to form and maintain a continuous electron conduction phase with sufficient mechanical strength. In the commercial LIBs, the dominant binder is polyvinylidene fluoride for the cathode (LiCoO2, LiFePO4, LiNixCotyMnzO2, etc.) and carboxyl methylcellulose/styrene‐butadiene rubber for the anode (graphite and Li4Ti5O12). However, these polymer binders have several drawbacks, particularly, a lack of electronic and lithium‐ion conductivities. Here, a novel organic/inorganic hybrid conductive binder (LAP‐rGO) for both the anode and cathode of LIBs is reported. The binder consists of 2D reduced graphene oxide sheets with anchored long alkane chains. Electrodes prepared using this binder exhibit sufficient high bond strength, fast electrolyte diffusion, high rate charge/discharge performance, and excellent cycling stability. Around 130 mAh g−1 capacity enhancement at 5C is demonstrated for LiFePO4 and Li4Ti5O12 electrodes owing to the combined improvement in electron and lithium ion transportation. LAP‐rGO bond graphite anode shows specific capacity beyond its theoretical value. Electrode slurries prepared using this new binder have superior processing and coating properties that can be prepared under a high humidity and dried using less energy. [ABSTRACT FROM AUTHOR]

Aqueous Mg ion batteries (AMIBs) show great potential in energy storage for their advantages of high capacity, abundant resource, and environmental friendliness. However, the development of AMIBs is limited due to the scarcity of suitable anode materials. In this study, a new polymer anode material (PNTAQ) with flower‐like nanosheet structure is synthesized for aqueous Mg‐Na hybrid‐ion battery (AMNHIB). PNTAQ possess carbonyl functional groups which can be oxidized and reduced reversibly in aqueous solution containing alkaline metal ions. PNTAQ displays a discharge specific capacity of 245 mAh g−1 at 50 mA g−1 in 1 M MgCl2 + 0.5 M NaCl electrolyte, which is much higher than that in single 1 M MgCl2 or 0.5 M NaCl electrolyte. Even cycling at 1000 mA g−1 for 1000 times, the capacity retention can still maintain at 87.2%. A full Mg‐Na hybrid‐ion cell is assembled by employing β‐MnO2 as cathode and PNTAQ as anode material, it exhibits a specific capacity of 91.6 mAh g−1 at 100 mA g−1. The polymer electrode material well maintains its framework structure during the discharge/charge cycling process of the hybrid‐ion battery. [ABSTRACT FROM AUTHOR]

To relieve the overwhelming pressure on fossil energy, aqueous magnesium ion batteries attracted tremendous attention owing to their low cost and high safety. However, the cathode materials are apt to occur lattice distortion because of the electrostatic interaction between magnesium ions and crystal. The 2×2 manganese octahedral molecular sieve with potassium ions and water located in the tunnels (K‐OMS‐2), utilized as a cathode material for chargeable magnesium ions batteries, is exposed to irreversible Mg2+ intercalation/deintercalation due to lattice distortion, which heavily damages the electrochemical properties and declines the capacity. Herein, we carry out an ion doping strategy to overcome the above issues, leading to an enhanced Mg Mg2+ storage behavior. The Nb or V cation is successfully doped into K‐OMS‐2 by a facile reflux method under room temperature. The specific surface area is enlarged by the addition of cations, which promise a large electrode‐electrolyte contact area. The Nb and V doped K‐OMS‐2 present a capacity of 252.6 and 265.9 mAh/g at 20 mA/g, respectively. This work demonstrates an ion doping approach toward exploiting the stable and high‐capacity Mg‐ion battery cathode and provides potential cathode materials for a large‐scale aqueous Mg‐ion‐based energy storage system. [ABSTRACT FROM AUTHOR]

Aqueous Mg‐ion batteries (MIBs) lack reliable anode materials. This study concerns the design and synthesis of a new anode material – a π‐conjugate of 3D‐poly(3,4,9,10‐perylenetracarboxylic diimide‐1,3,5‐triazine‐2,4,6‐triamine) [3D‐P(PDI‐T)] – for aqueous MIBs. The increased aromatic structure inhibits solubility in aqueous electrolytes, enhancing its structural stability. The 3D‐P(PDI‐T) anode exhibits several notable characteristics, including an extremely high rate capacity of 358 mAh g−1 at 0.05 A g−1, A 3D‐P(PDI‐T)‖Mg2MnO4 full cell exhibits a reversible capacity of 148 mAh g−1 and a long cycle life of 5000 cycles at 0.5 A g−1. The charge storage mechanism reveals a synergistic interaction of Mg2+ and H+ cations with C−N/C=O groups. The assembled 3D‐P(PDI‐T)‖Mg2MnO4 full cell exhibits a capacity retention of around 95 % after 5000 cycles at 0.5 A g−1. This 3D‐P(PDI‐T) anode sustained its framework structure during the charge–discharge cycling of Mg‐ion batteries. The reported results provide a strong basis for a cutting‐edge molecular engineering technique to afford improved organic materials that facilitate efficient charge‐storage behavior of aqueous Mg‐ion batteries. [ABSTRACT FROM AUTHOR]

Lithium metal anode is the most ideal candidate for next‐generation energy storage system. However, the uncontrolled dendrite growth, infinite volume expansion, and undesired side reactions lead to serious safety issues and hinder their potential application. Herein, a pre‐lithiation strategy is proposed to construct a high‐lithiophilic Cu‐Li2O matrix on commercial Cu foil. The in situ‐generated Li2O promises adequate nucleation sites and strengthens solid electrolyte interphase and lateral lithium deposition. Meanwhile, the existence of 3D matrix reduces the local current density. The synergy effect of Li2O and Cu suppresses the growth of lithium dendrites. As a result, Cu‐Li2O matrix reveals an enhanced lithium plating/stripping behavior with Coulombic efficiency of 98.46% after 270 cycles. The symmetrical cell assembled by Li‐plated electrodes displays a prolonged lifespan of 1400 h. The work demonstrates a scalable and effective approach for modified current collectors toward stable Li metal anode. [ABSTRACT FROM AUTHOR]

The article titled "Enhancing Electrochemical Performance through Swift Functional Group Tuning of MXenes" discusses the use of flash Joule heat (FJH) technology to modify the surface of MXene materials. The researchers demonstrate that this technique can be used to cut and modulate the terminations on the MXene surface within 1 second. The study shows that certain terminations, specifically VI A and V A, outperform VII A terminations in terms of electrochemical performance. For more information, readers can refer to the research article by Y.-Z. Fang, D. Cao, and their colleagues. [Extracted from the article]

As a recently emerging group of 2D materials, MXene has attracted extensive attention in the energy storage field in recent years owing to their outstanding features. However, the notorious issues of inevitable oxidation stability and surface‐to‐surface self‐restacking for MXene significantly prevent its further wide‐ranging application. Herein, the 3D macroporous oxidation‐resistant Ti3C2Tx MXene/graphene/carbon nanotube (MRC) hybrid hydrogels are prepared by a simple gelation method assisted by l‐cysteine as crosslinker and l‐ascorbic acid (VC) as reductant. Benefitting from the effectively alleviated restacking, excellent electrical conductivity, and the 3D inter‐crosslinked macroporous architecture, as a supercapacitor electrode, the obtained MRC aerogel exhibits a superior specific capacitance of 349 F g−1, unparalleled rate capability (52.0% at 3000 mV s−1) and amazing cyclic stability (retention of 97.1% after 100 000 cycles). Moreover, the 3D MRC‐30 aerogel exhibits an impressive oxidation‐resistant performance with just a 9.3% increase in electrical resistance after storing in ambient condition for 60 days, effectively alleviating the oxidation problem of MXene. This work demonstrates a new method for construction of 3D oxidation‐resistant MXene hydrogel, shedding new light on the promising applications of MXene materials, especially in high humidity and oxygen environment. [ABSTRACT FROM AUTHOR]

Sodium‐ion hybrid capacitors (SIHCs) are considered a prospective alternative to lithium‐ion batteries (LIBs) since there are rich and available sodium reserves. Here, nitrogen‐doped carbon tubes (N‐MJ) derived from metaplexis japonica fluff are prepared by using a facile method of etching and peeling the fluff with urea to prepare a Na+ storage anode. With prominent traits in terms of structure and a high nitrogen content (11.08 %), N‐MJ exhibits exceptional Na+ storage performance with a high reversible capacity (390.9 mAh g−1 at 50 mA g−1) and excellent long‐term circulation (208.1 mAh g−1 after 2650 cycles at 1 A g−1). Systemic kinetic analysis manifests that the extraordinary performance is responsible for the large‐scale capacitance control. Furthermore, the SIHCs assembled by using N‐MJ and activated carbon (AC) presents a maximum energy density of 111.4 Wh kg−1 (at 445.8 W kg−1) and power density of 2455.2 W kg−1 (at 34.1 Wh kg−1). Notably, the developed SIHCs maintain a 100 % capacity retention rate at 1 A g−1 after 5000 cycles. Overall, our work not only provides a good choice for storage Na+ anode materials, but also supplies a feasible method for the recycling of waste biomass. [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (MoO3) has recently aroused intensive interest as a renowned conversion‐type anode of Li‐ion batteries (LIBs). Nevertheless, the inferior rate capability, sluggish reaction kinetics, and fast capacity decay during a long‐term charge/discharge process seriously inhibits large‐scale commercial application. Herein, abundant oxygen vacancies and MXene nanosheets are elaborately introduced into MoO3 nanobelts through hydrazine reduction and electrostatic assembly to accelerate the ionic and electronic diffusion/transport kinetics for LIBs. Benefitting from the accelerated ion diffusion kinetics, enhanced electrical conductivity, and additional active sites induced by oxygen vacancies as well as the robust interfacial contact, the prepared MoO3−x/MXene heterostructure exhibits excellent lithium‐ion storage performances. First‐principles calculations indicate that the adsorption of Li+ ion and the electrical conductivity are significantly enhanced for the MoO3−x/MXene heterostructure. Thus, the composite exhibits high reversible capacity of 1258 mAh g−1 at 0.1 A g−1 for Li‐ion storage and retains 474 mAh g−1 at 10 A g−1, remarkably higher than those of the previously reported MoO3‐based anode materials. More importantly, the composite is fabricated with commercial LiFePO4 into a full LIB, which displays an unparalleled energy density of 330 Wh kg−1. [ABSTRACT FROM AUTHOR]