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Rechargeable Zn‐based batteries provide a compelling supplement to subsistent energy storage devices owing to their high energy density, good safety, and low cost. Nevertheless, inherent imperfections such as dendrite growth, side reactions, and andante reaction kinetics, severely impede their commercialization. As new 0D nanomaterials, carbon dots (CDs) with unique characteristics and excellent electrochemical activity, exhibit promising potential exploitation in electrochemistry and electrocatalysis areas. Herein, the adhibition of CDs in resolving the aforementioned drawbacks of Zn‐based batteries is introduced. To begin with, concepts, physicochemical properties, and synthetic methods of CDs are discussed. Next, recent developments and advances exploiting CDs in respectively ameliorating the performance of the Zn anode, the cathode, and electrolytes of Zn ion batteries and bifunctional electrocatalytic activities including oxygen reduction reaction and oxygen evolution reaction for Zn‐air batteries, are roundly reviewed and minutely generalized. Finally, current challenges and prospects are surveyed as well, aiming to offer a reference for the blossom of advanced Zn‐based batteries. [ABSTRACT FROM AUTHOR]

Zinc‐ion batteries (ZIBs) have become a global research hotspot in recent years due to their eco‐friendliness, safety, abundant resources, and low cost. However, some significant challenges seriously affect their overall performance, thus hindering their further development and practical applications. Recently, multifunctional and adjustable 2D carbides and nitrides (MXenes) are extensively used for the modification of ZIBs, and fruitful achievements are achieved. In order to make a systematic understanding of these studies, it is highly desirable to provide an overview of MXenes based on their modification methods and action mechanisms. In this review, a basic introduction to ZIBs and MXenes is presented and the main modification approaches of MXenes in solving the issues of ZIBs are discussed in detail, including activation and composite strategies of the cathode, interface engineering, structural optimization, and zinc metal‐free anode strategy of the anode, solid‐state strategy of the electrolyte, and functionalized strategy of the separator. Importantly, the functions and related mechanisms of MXenes in various components of ZIBs are analyzed in depth. Finally, the pathways for MXenes in solving the issues of ZIBs are summarized, and their future directions are prospected. [ABSTRACT FROM AUTHOR]

Garnet solid state electrolytes (SSEs) have emerged as propitious candidates for solid‐state batteries (SSBs) with exceptional ionic conductivity and excellent (electro)chemical stability. However, the Li|garnet interface contact deterioration still remains a major challenge resulting in Li dendrite propagation. Herein, a method is proposed to strengthen the adhesion of garnet SSE and Li by incorporating Sr3N2 into the Li metal. Density functional theory (DFT) calculations reveal that the interfacial formation energy of Li|garnet is decreased by the obtained Li‐Sr‐N (LSN) composite, which can enable a shift from poor contact to intimate bonding at the Li|garnet interface and a homogenous Li+ flux as well as electric field distribution. Simultaneously, the produced Li3N and LiSrN, which are known for their strong Li adsorption affinity and rapid Li+ transfer kinetics, actively govern the Li plating process. Thereby this rational design brings a notable reduction in interfacial impedance (4.5 Ω cm2), along with the increased critical current density (1.3 mA cm−2) and enhanced cycle stability (1200 h at 0.3 mA cm−2). Furthermore, The LFP|garnet|LSN full cell has demonstrated remarkable cycling performance (95.9% capacity retention after 200 cycles at 1 C) and favorable rate capability (150.2 mAh g−1 at 0.1 C and 134.9 mAh g−1 at 1 C). The research provides a new sight into lithium modification that can restrain Li|garnet interface deterioration and lay the groundwork for future advancements in high‐performance garnet‐ based SSBs. [ABSTRACT FROM AUTHOR]

Niobium oxides have fascinated numerous interests for ultrafast sodium‐ion batteries due to their impressive stability, fast pseudocapacitive kinetics, and high safety features. However, the poor intrinsic electronic conductivity and unrevealed mechanisms largely limit their further applications. Here, inspired by density functional theory (DFT) calculations, the introduction of conductor heterostructure (Nb2O5/NbSe2) can largely decrease the bulk phase inserted energy of Na+ from 9.88 to −3.54 eV, as well as promote the delocalization of electron, greatly improving the electrical conductivity of Nb2O5. As expected, the as‐obtained orthorhombic niobium pentoxide (T‐Nb2O5‐x‐NbSe2@C) delivers a high conductivity of 3.69 S cm−1, exhibiting a great improvement of four orders magnitude than that of the parent Nb2O5 (1.87 × 10−4 S cm−1). Impressively, T‐Nb2O5‐x‐NbSe2@C possesses a high reversible capacity of 249 mAh g−1 at 0.1 A g−1, as well as excellent rate performance of 63 mAh g−1 at 5.0 A g−1, nearly twins the capacity of parent porous Nb2O5. Furthermore, the periodic evolutions of the main peaks for targeted electrodes during repeated charging/discharging processes have been further revealed by in situ XRD, demonstrating a highly reversible inserted/extracted storage mechanism of Na+. This work provides a novel method to improve the conductivity of materials by constructing conductor heterojunction. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) are promising candidates for grid‐energy storage due to their safety and cost‐effectiveness. However, the detrimental hydrogen evolution reaction (HER) and dendrite growth on Zn‐metal anodes severely limit their applications. Herein, trace hydrophobic hyamine (HQA, 0.78 mmol L−1) is introduced as an electrolyte additive to improve the electrochemical performance of the Zn anode. Experiments and theoretical calculations revealed that cationic HQA can preferentially adsorb onto the anode surface to inhibit the HER and promote the uniform distribution of Zn ions by forming a water‐lean electric double layer (EDL). Moreover, the oriented adsorption of HQA induced exposure of the Zn (002) plane and prevented dendrite growth. Therefore, the symmetric cells using the HQA‐containing electrolyte exhibited stable cycle performance for more than 1600 h. Even at a high‐density current of 5 mA cm−2, it has a high cumulative capacity of 3250 mAh cm−2. It exhibited an excellent deep‐discharge performance (80%) with a stable cycle for 175 h. The Zn||NH4V4O10 full cell exhibited a high specific capacity and cycle stability at 4.0 A g−1 due to the excellent reversibility of Zn anode. These results provide a new and low‐cost approach for electrolyte design and EDL optimization of high‐performance zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

The uneven zinc‐ion flux and interfacial contact between the anode and electrolyte trigger malignant dendrites and byproducts, significantly hindering the practical application of zinc‐metal batteries. Herein, a H‐bonded supramolecular organic framework (HSOF) is proposed to help regulate Zn2+ flux and stabilize interfacial chemistry. The self‐assembled supermolecule structures by in‐plane H‐bond networks firmly trap water molecules to assist Zn2+ de‐solvation and block interfacial corrosion. The abundant polar groups provide strong guidance for Zn2+ distribution, ensuring homogeneous, and rapid ion transport‐deposition kinetics. Meanwhile, the π–π stacked space‐layout structure affords preferred Zn(002) plane stacking for smooth and flat growth. Benefiting from these advantages, the HSOFs are employed on Zn surface for interfacial adjustment and on separator decoration for spatial manipulation, successfully realizing an overall "interface‐space" dual‐regulation effect. It delivers over 3000 h for the HSOF@Zn anode in symmetric cell and up to 5000 h for HSOF‐decorated separator in Zn||Zn symmetric cell, respectively. The HSOF@Zn||V2O5 full cell with the HSOF‐decorated separator demonstrates enhanced capacity retention of 92.7% after 2500 cycles at 5 A g−1. The full cell can be easily scaled up into a pouch cell, which still has a capacity retention rate of 94% after 1000 cycles. [ABSTRACT FROM AUTHOR]

Antimony（Sb） has high theoretical specific capacity and moderate reaction potential, but poor cycling stability and rate performance caused by large volume expansion and sluggish reaction kinetics limit its development in alkali‐ion batteries. The construction of carbon/Sb composites can solve this problem, but the traditional single carbon composite and poor Sb/carbon interface have limited promotion. Here, under the guidance of theoretical calculations, a strategy of hierarchical double carbon composite is proposed to enhance the performance of Sb anode, and systematically reveal the lithium/sodium ions (Li+/Na+) storage mechanism of Sb in complex composite system. Sb nanoparticles (Sb NPs) are encapsulated in carbon sphere matrix with strong interfacial chemical bond to form the first level composite material, and then the highly conductive and mechanically strong graphene is used as a three‐dimensional skeleton network to connect the first level composite to form the second level composite material. The hierarchical double carbon/Sb composite exhibits excellent rate (228 mAh g−1 @ 20 A g−1) and long cycling performance (373.7 mAh g−1 @ 2 A g−1 after 2200 cycles, capacity retention of 93.1%). This work may expand structural design and interface regulation of Sb/C composites and providing theoretical guidance for metal anodes development. [ABSTRACT FROM AUTHOR]

Captured by the remarkable environmental/economic value, recycling spent LiFePO4 has attracted numerous attention. However, restricted by diverse failure mechanisms and different particle‐sizes/active‐sites, recycling strategies still suffer from uneven repairing results and poor accessibility. For promoting their application in commercial systems, the uniform physical‐chemical properties are urgent for regenerated samples. Herein, by tailoring oxidation‐reduction manners, the homogeneous cathode materials can be prepared, displaying uniform particle size and restored lattice. The capacity of as‐optimized samples can be kept ≈141.5 mAh g−1 at 1.0 C, and 137 mAh g−1 with a retention of 92% after 300 cycles at 2.0 C. After Kg‐scale experiments, the pouch full‐cell (LFP‐500 vs recovered graphite) delivers ≈4200 mAh capacity, with considerable cycling stability (retention 96.83%, after 500 loops). Importantly, the detailed mechanism of oxidation/reduction‐conditions is investigated, especially their lattice reconstitution and ions‐ diffusion behaviors. Supported by kinetic analysis and DFT calculations, the fascinating stability of LFP‐500 is further proved, mainly derived from the accelerated Li‐diffusion behaviors. Compared to traditional recovering manners, oxidation/reduction process displays low cost, energy‐consumption, and pollution, accompanied with considerable large‐scale application potential. Given this, this work is anticipated to illustrate the in‐depth mechanism of lattice‐reconstruction, while offering significant strategies for large‐scale and homogenized regeneration. [ABSTRACT FROM AUTHOR]

Hard carbon (HC) is widely regarded as the most promising anode material for sodium‐ion batteries (SIBs). For improving the sodium storage capacity of HC anode, current research primarily focuses on the high‐voltage slope region. Actually, increasing the storage capability in the low‐voltage plateau region is more important for enhancing the energy density of full cells. Therefore, in this study, HC anode with rich closed pore structure is designed and constructed with the help of carbon dots (CDs), and it is demonstrated that the presence of closed pore structure can provide more sodium storage sites in the plateau region, resulting in an obvious increase of sodium storage capacity. Moreover, the pore‐filling and intercalation mechanism for sodium storage in plateau region is revealed by in situ Raman spectroscopy and ex situ transmission electron microscopy (TEM). It is worth noting that the increase in capacity induced by closed pore‐filling is not accompanied by a decrease in initial coulombic efficiency (ICE), due to the fact that the introduction of closed pores does not increase the contact area between electrode and electrolyte. This work presents novel concepts for the structural design of HC and provides valuable insights into the effective utilization of plateau region in SIBs. [ABSTRACT FROM AUTHOR]

Further commercialization of Ni‐rich layered cathodes is hindered by severe structure/interface degradation and kinetic hindrance that occur during electrochemical operation, which leads to safety risks and reduced range in electric vehicles (EVs). Herein, by selecting elements with different solubility properties, a multifunctional strategy that synchronously fabricates perovskite‐type SrZrO3 coating and Sr/Zr co‐doping is employed to strengthen the structure/interface stability and the Li+ transport mobility of LiNi0.85Co0.10Mn0.05O2 (NCM). Perovskite‐type SrZrO3 protective layers formed on the particle surface can substantially mitigate the unexpected interfacial side reactions and surface phase transitions. In addition, a robust crystal framework is constructed by optimizing local O coordination through the introduction of strong Zr−O bonds. Notably, Li+ diffusion kinetics is effectively improved due to expanded cell parameters and O‐Li‐O slab spacing with the incorporation of large‐diameter Sr pillar ions, as revealed by X‐ray diffraction. As a result, the Sr/Zr‐modified NCM achieves a remarkable capacity retention of 99.4% after 200 cycles at 1 C, and a high rate capacity of 168.9 mAh g−1 at 10 C. This work opens new avenues to develop high‐performance NCM cathodes with high energy and high power for EVs with long calendar life. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been proposed as novel fillers for constructing polymer solid electrolytes based composite electrolytes. However, MOFs are generally used as passive fillers, in‐depth revealing the binding mode between MOFs and polyethylene oxide (PEO), the critical role of MOFs in facilitating Li+ transport in solid electrolytes is full of challenges. Herein, inspired by density functional theory (DFT) the 2D‐MOF with rich unsaturated metal coordination sites that can bind the O atom in PEO through the metal–oxygen bond, anchor TFSI− to release Li+, resulting in a remarkable Li+ transference number of 0.58, is reported according well with the experimental results and molecular dynamics (MD) simulation. Impressively, after the introduction of the 2D‐MOF, the Li+ can rapidly hop along the benzene ring center within the 2D‐MOF plane, and the interface between the benzene ring and PEO can also serve as a fast Li+ migration pathway, delivering multiple ion‐transport channels, which present a high ion conductivity of 4.6 × 10−5 S cm−1 (25 °C). The lithium symmetric battery is stable for 1300 h at 60 °C, 0.1 mA cm−2. The assembled lithium metal solid state battery maintains high capacity of 162.8 mAh g−1 after 500 cycles at 60 °C and 0.5 C. This multiple ion‐transport channels approach brings new ideas for designing advanced solid electrolytes. [ABSTRACT FROM AUTHOR]

Fe‐Mn based layered oxides are recognized as promising cathode materials for sodium‐ion batteries (SIBs) with high capacities and earth‐abundant ingredients. However, their real‐world applications are still constrained by fast capacity decay accompanied with the requirements of deeper insights into the principles behind. Herein, taking O3‐NaxFe1/2Mn1/2O2 as a classic sample, the capacity fading mechanism of Fe‐Mn based layered oxides is comprehensively investigated through combined techniques. For the first time, it is revealed that Fe migration is merely triggered after the oxidation of ≈0.3 mol Fe3+ based on solid proofs from ex situ X‐ray absorption spectroscopy and Mössbauer spectroscopy, which implies the crucial role of the accumulated structural distortion induced by Jahn–Teller active Fe4+. O3‐P3 phase transition during cycling is obviously constrained along with Fe migration as evidenced by in situ/ex situ X‐ray diffraction, well interpreting the intensified polarization and the resulting large capacity loss. More importantly, within the desodiation depth (≈80% of sodium extraction) where Fe migration is almost absent, the capacity fading is dominantly rooted in the Fe4+ activated and Mn‐dissolution aggravated surface passivation as confirmed by mass/X‐ray spectroscopies and electrochemical analysis. These renewed understandings of the fast capacity decay in Fe‐Mn based layered oxides offer clearer clues for designing desirable cathodes for SIBs. [ABSTRACT FROM AUTHOR]

Attracted by high energy density and power density, metal‐sulfides anodes have promising application prospects in fast charging batteries. However, they still suffer from low electrical conductivity and sluggish electrochemical kinetics, resulting in poor fast charging capacity. Herein, spindle‐like antimony sulfide (Sb2S3) is rationally tailored with favorable (hk1) crystal orientation and rich S‐vacancies using a simple hydrothermal method, which improve electric conductivity significantly. Triggered by S‐vacancies lattice defects, SbOC interfacial bonds and S‐doped carbon layer are built successfully. Under their multiple‐controlling synergistic effects, electrochemical kinetics and reaction reversibility are promoted effectively. As expected, Sb2S3/HTAB@C show high average initial coulombic efficiency of 86.12%, and deliver 624.5 and 428.4 mAh g−1 after cycling 100 cycles at 10.0 and 30.0 A g−1 respectively in Li‐ion batteries (LIBs). Electrochemical kinetic analysis and theoretical calculations indicate that superior ultrafast charging capacity originates from quickened interfacial electron/ions transferring and alleviates electrochemical polarization. Ex situ technologies powerfully prove good stability of (hk1) orientation, SbOC bonds and S‐doped carbon layer. Notably, full LIBs of SS/H@C versus LiFePO4@C display 500.9 and 398.3 mAh g−1 at 5.0 and 10.0 A g−1, respectively. This study is anticipated to open avenue to develop advanced metal‐sulfides anodes for fast charging batteries. [ABSTRACT FROM AUTHOR]

The extensive applications of spinel LiMn2O4 (LMO) are severely plagued by grievous capacity degradation and structural collapse, mainly ascribed to deleterious Jahn−Teller distortion and subsequent dissolution of Mn2+. Herein, highly stable LMO with atomic interlocking effect is rationally designed via engineering Al into the unoccupied 16c sites. The local coordination environment of the surficial MnO6 octahedron is reconstructed by robust Al−O band coherency, giving strengthened lattice oxygen skeleton and constraining heterophase evolution with the suppression of Jahn−Teller distortion, validated by theoretical calculations coupled with synchrotron X‐ray absorption spectrum. Concomitantly, with the occupation of Al in interstitial site, the migration of Mn is effectively restrained, directly observed by scanning transmission electron microscopy, leading to the inhibition of inactivation as well as dissolution loss of Mn. Resultantly, splendid long cycling stability of Al‐LMO after 1000 loops with only 0.019% capacity fading per cycle is presented. Given this, this elaborate study can provide an ingenious avenue for regulating the structure/interface chemistry architecture in electrode materials. [ABSTRACT FROM AUTHOR]

The rational design of bifunctional catalysts with excellent activity and stability toward the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is essential for rechargeable Zn‐air batteries (ZABs). In this study, a facile coordination bridging strategy is proposed to construct bifunctional Co‐CoN4 hybrid active sites embedded in porous N‐rich carbon nanolamellas (denoted as Co‐CoN4@NCNs) for both the ORR and OER. Synchrotron X‐ray absorption spectroscopy and density functional theory calculations reveal that the increased intrinsic ORR/OER activities can be attributed to the efficient interfacial charge transfer between the atomic CoN sites and metallic Co sites due to their robust electronic correlation. In situ Raman spectroscopy confirms that the OER activity depends on the CoOOH intermediates formed during the reaction. Co‐CoN4@NCNs exhibits superior bifunctional catalytic performance for the ORR (E1/2 = 0.83 V) and OER (η = 310 mV at 10 mA cm−2) conducted in alkaline media. The assembled rechargeable Co‐CoN4@NCNs‐based ZAB displays an open‐circuit voltage of 1.47 V, peak power density of 118.8 mW cm−2, specific capacity of 776.7 mAh g−1, and outstanding cycling stability over 1500 cycles. The regulation of the interfacial electronic properties can contribute to the rational design of bifunctional electrocatalysts used in rechargeable metal‐air batteries. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) have appealed increasing attention due to the inexpensive K‐element resources and satisfactory electrochemical properties. Presently, there are still challenges for developing desirable anode materials. Two‐dimensional metal sulfides exhibit high specific capacity as host for PIBs, yet the dissolution and agglomeration of unstable reaction intermediate KxSy (K2S, K2S5) inescapability induces large loss of active ingredients and poor reactions reversibility, leading to inferior lifespan. Herein, polar polysulfide VS4 is introduced into SnS nanosheets with constructing layered VS4/SnS heterostructure anchored in graphene scaffold (VS4/SnS@C). In this framework, VS4 with unsaturated bridging (S2)2– can act as the anchoring sites to stabilize intermediates KxSy with efficient entrapment effects. Moreover, the heterostructure can maintain layered SnS and regulate the distribution of KxSy with high conversion reversibility. The reaction reversibility and intermediate absorptivity are enhanced, as confirmed by in situ X‐ray diffraction analysis and theoretical calculations. Consequently, the VS4/SnS@C electrode exhibits ultra‐long lifespans, which achieves a capacity of 168.4 mAh g–1 at 1 A g–1 after 6000 cycles. This strategy of heterostructure design facilitates the understanding of K‐storage mechanisms and significantly enhances the reaction reversibility, providing a thought to address the challenges in metal sulfide anodes toward the development of high‐performance PIBs. [ABSTRACT FROM AUTHOR]

Prelithiation/presodiation techniques are regarded as indispensable procedures in electrochemical energy storage (EES) systems, which can effectively compensate irreversible capacity loss, raise working voltage, and increase Li+/Na+ concentration in the electrolyte. Various prelithiation/presodiation methods have been successfully exploited and a revolutionary impact has been achieved through the utilization of prelithiation/presodiation techniques. It is well acknowledged that different prelithiation/presodiation strategies possess their own specific mechanisms, which play vital roles in the advancement of EES systems. However, there has rarely been systematical reviews about the concept and progress of prelithiation/presodiation techniques. Hence, in this review various prelithiation/presodiation approaches are comprehensively analyzed and summarized, and in‐depth prelithiation/presodiation behaviors and other innovative applications (including optimization of separators, amelioration of binders, regeneration of spent batteries) are discussed in detail. Finally, suggested future directions of prelithiation/presodiation techniques are proposed and it is expected that these prelithiation/presodiation techniques could provide guidance for construction of advanced EES systems and propel the commercialization process with a focus on safety considerations. [ABSTRACT FROM AUTHOR]

Fabrication of Bi/C composites is a common approach to alleviate the severe volume expansion of Bi alloy‐based anodes with a high theoretical capacity of 3800 mAh cm−3 for lithium ion batteries (LIBs). However, the complicated and tedious synthetic routes restrict its large‐scale preparation and practical applications. Herein, a spongiform porous Bi/C composite (marked as Bi@PC) through the carbothermal reduction (CTR) method is constructed. Bi nanodots are in situ confined in a porous carbon substrate activated by the gases produced from the decomposition of the sodium phytate precursor, indicating the feasibility and simplicity of this route. In charge/discharge processes, Bi nanodots embedded in carbon matrix are effective enough to accommodate the strain change and shorten the migration distance. In addition, the porous carbon forms an efficient conductive network for electron shutting. When utilized for lithium storage, a superb capacity of 520 mAh g−1 at 0.2 A g−1 after 100 cycles and a satisfying long cyclic stability of 380 mAh g−1 at 0.5 A g−1 after 500 cycles are achieved. The excellent Li‐storage performance and this handy preparation method jointly make this Bi/C composite a potential anode for LIBs, and could inspire the preparation of other alloy‐type anodes. [ABSTRACT FROM AUTHOR]