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TiO2 with the merits of non‐toxicity, high stability, strong redox capability, and low cost, has garnered considerable attention in the fields of renewable energy. However, the practical application is limited by the rapid recombination of photogenerated electron–hole pairs, posing a challenge to enhance electron utilization without compromising catalytic activity. Herein, S‐scheme TiO2@Co(OH)F‐Pt heterojunction through a simple hydrothermal and photo‐deposition method is constructed. The experimental tests and theoretical computation indicate that Co(OH)F possesses a smaller work function and a more negative conduction band (CB) position, significantly accelerating the separation of photogenerated charge carriers. Furthermore, the built‐in electric field, band bending between TiO2 and Co(OH)F, and the electron sink of Pt nanoparticles, facilitate the reduction of protons to hydrogen. The as‐prepared TiO2@Co(OH)F‐Pt exhibits high‐performance solar hydrogen evolution with an evolution rate of 1401 µmol h−1. The apparent quantum yield (AQY) is determined to be 22.8% at a single wavelength of 365 nm. After reacting 12 h for three cycles, no noticeable performance degradation occurs, showing good stability of the catalyst. This work provides a rational strategy for the design of heterojunction photocatalysts for driving the production of new energy and useful chemicals. [ABSTRACT FROM AUTHOR]

Parasitic electrolyte reactions and dendrite growth make Zn metal anodes with high Zn utilization rates (ZURs) more inaccessible, holding back the advance of aqueous zinc metal batteries (AZMBs). Here, sodium isoascorbate (SIA) is introduced to aqueous electrolytes as a self‐deoxidizing and self‐dehydrogenating additive. Coexisting C6H7O6−/C6H5O6− couple spontaneously captures dissolved oxygen and eliminates generated hydrogen by acting as a redox buffer, which leads to the creation of antioxidant Interfaces due to an in situ formed ZnCO3‐dominated solid electrolyte interphase (SEI). This SEI enables the (100) faceted electrode with dendrite‐free and non‐corrosive Zn plating/stripping, thus yielding a Coulombic efficiency of 99.7% up to 1100 h at 5 mAh cm−2, as well as a stable cycle sustaining for over 335 h under a high ZUR of 85.5%. Full‐cell properties are demonstrated by matching a poly(3,4‐ethylenedioxythiophene) intercalated vanadium oxide (PEDOT‐V2O5) cathode, which harvests a high capacity of 302 mAh g−1 (at 0.01 A g−1) and holds 94.2% capacity retention over 600 cycles (at 1 A g−1) under practical conditions (N/P = 4.2 and E/C = 7.6 µL mg−1). These findings provide a new solution for electrolyte design for industrializing AZMBs. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting to produce green hydrogen offers a promising technology for renewable energy conversion and storage, as well as realizing carbon neutrality. The efficiency, stability, and cost of electrocatalysts toward hydrogen evolution reaction (HER) and electrocatalytic overall water splitting (EOWS) at large current densities are essential for practical application. In this review, the key factors that determine the catalytic performance of electrocatalysts at large current densities are summarized from the angel of thermodynamic and kinetic correlation. The corresponding design strategies are presented. The electronic structure and density of active sites that affect the adsorption/desorption of intermediates are considered as the thermodynamic aspects, while charge transfer and mass transport capabilities closely associated with electrode resistance and intermediate diffusion are assigned as kinetic effects. Recent development of bifunctional and integrated electrocatalysts toward EOWS is also discussed in detail. Finally, the perspective and direction on the electrocatalytic water splitting under large current density are proposed. This comprehensive overview will offer profound insights and guidance for the continued advancement of this field. [ABSTRACT FROM AUTHOR]

Hard carbon (HC) is subjected to low initial Coulombic efficiency (ICE) and unsteady solid electrolyte interphase (SEI), which limits the energy density and cycling performance. Meanwhile, studies related to emerging chemical presodiation have specifically focused on proper redox potential and overlooked its safety hazard. To address these drawbacks of HC and chemical presodiation, a series of high‐safety chemical presodiation solutions based on tetraethylene glycol dimethyl ether (TEGDME) are proposed for uniform and fast presodiation of HC and Bi anodes. Among them, Na‐4‐methylbiphenyl in TEGDME solution exhibits the lowest redox potential (0.146 V vs Na+/Na), which achieves the inhibition of initial irreversible sodium uptake. Meantime, the potential‐driven decomposition of fluoroethylene carbonate endows presodiated HC (pNa‐HC) a fast‐ion conducting and robust F‐rich SEI. Accordingly, pNa‐HC delivers an ideal ICE of 99.1% compared to HC (65.28%). Meanwhile, pNa‐HC exhibits significantly enhanced rate performance and cycling life (193.39 mAh g−1 after 2300 cycles at 1000 mA g−1) benefiting from reduced kinetic energy barriers. When pNa‐HC pairs with Na3V2(PO4)3 cathode, the full cell demonstrates a desirable ICE of 91.25%. This work provides a novel and universal solvent design strategy to realize high‐safety chemical pre‐metallation. [ABSTRACT FROM AUTHOR]

The advanced aqueous zinc–ion batteries (AZIBs) are still challenging due to the harmful reactions including hydrogen evolution and corrosion. Here, a natural small molecule acid vitamin C (Vc) as an aqueous electrolyte additive has been selectively identified. The small molecule Vc can adjust the d band center of Zn substrate which fixes the active H+ so that the hydrogen evolution reaction (HER) is restrained. Simultaneously, it could also fine–tune the solvation structure of Zn ions due to the enhanced electrostatics and reduced Pauli repulsion verified by energy decomposition analysis (EDA). Hence, the cell retains an ultra–long cycle performance of over 1300 cycles and a superior Coulombic efficiency (CE) of 99.5 %. The prepared full cells display increased rate capability, cycle lifetime, and self–discharge suppression. Our results shed light on the mechanistic principle of electrolyte additives on the performance improvement of ZIBs, which is anticipated to render a new round of studies. [ABSTRACT FROM AUTHOR]

Engineering high‐performance oxygen evolution reaction (OER) anode material with high activity, selectivity, and strong robustness against chloride corrosion is critical to advance seawater electrolysis for large‐scale production of H2, yet a daunting challenge. Herein it is reported for the first time, the engineer of a multilayered electrode consisting of Ni foam‐supported Ni3N porous nanosheet array decorated with NiFe‐phytate coordination complex overlayer (NF/Ni3N@NiFe‐PA) via a facile interfacial coordination assembly, for remarkably boosted and sustained OER in alkaline seawater electrolysis. Benefitting from regulated electronic state by synergism between Ni and Fe species, boosted proton‐coupled electron transfer via accelerating proton movement with the aid of incorporated phytic acid as proton transfer relay, and promoted mass transfer rendered by unique superhydrophilic and superaerophobic property, the resulting NF/Ni3N@NiFe‐PA demonstrates prominent OER activity in seawater. Impressively, integrating anticorrosive Ni3N with NiFe‐PA complex and in situ generated NiFeOOH can collaboratively contribute to chloride repelling, leading to exceptional corrosion resistance of the electrode. This work affords a novel paradigm to engineer active and corrosion‐resistive anode for selective OER in saline water electrolysis via simultaneous geometric and electronic structural manipulation. [ABSTRACT FROM AUTHOR]

Constructing a stable solid electrolyte interphase (SEI) at the electrode–electrolyte interface is powerful for optimizing the battery performance. However, studies related to interface chemistry have particularly focused on engineering electrolytes and overlooked regulating electrode materials. Here, this study reports that the B‐doped Bi interconnected nanoparticles (B─Bi) are prepared by a facile and effective chemical reduction reaction. The B doping helps to catalyze the electrolyte decomposition and more NaF formation on the electrode surface, which facilitates a stable uniform SEI with enhanced mechanical stability. Such a robust SEI layer can inhibit the further decomposition of electrolytes and promote the interfacial Na+ transfer. The B─Bi offers a reversible capacity of 403.1 mAh g−1 at 1.0 A g−1 and a high rate capability of 203 mAh g−1 at 80 A g−1. Moreover, the B‐doping method also finds its viability to stabilize SEI in Sb material. This study demonstrates a new strategy for engineering the interface chemistry toward stable SEI and excellent performance. [ABSTRACT FROM AUTHOR]

Pt‐based nanocrystals with tunable electronic structure and optimized atom efficiency are essential for boosting the hydrogen evolution reaction (HER) performance and further industrial application. However, the synthesis of uniform and ordered nanocrystals is still a challenge due to the uncontrollable size growth of metal particles, restricting the active sites toward the desired catalytic activity. Herein, the synthesis of ultrafine bimetal PtMo nanocrystals on N‐doped carbon (PtMo‐NC) through an anchoring‐sites engineering strategy is reported, in which the N‐rich carbon can provide abundant sites to anchor the metal atoms and suppress the over aggregation. The PtMo‐NC catalyst exhibits superior HER performance in both alkaline and acidic conditions, delivering a smaller overpotential (80 mV and 63 mV) at a current density of 100 mA cm−2 in alkaline and acidic media. Theoretical calculations reveal that the introduction of Mo atom into Pt can reduce the energy barrier of water molecule dissociation and optimize the H intermediate absorption strength on Pt sites, thus boosting the catalytic HER performance. This study offers a universal strategy to design ultrafine nanocatalysts to achieve high‐efficiency electrocatalysis. [ABSTRACT FROM AUTHOR]

Constructing atom‐clusters (ACs) with in situ modulation of coordination environment and simultaneously hollowing carbon support are critical yet challenging for improving electrocatalytic efficiency of atomically dispersed catalysts (ADCs). Herein, a general diffusion‐controlled strategy based on spatial confining and Kirkendall effect is proposed to construct metallic ACs in N,P,S triply‐doped hollow carbon matrix (MACs/NPS−HC, M=Mn, Fe, Co, Ni, Cu). Thereinto, FeACs/NPS−HC with the best catalytic activity for oxygen reduction reaction (ORR) is thoroughly investigated. Unlike the benchmark sample of symmetrical N‐surrounded iron single‐atoms in N‐doped carbon (FeSAs/N−C), FeACs/NPS−HC comprises bi‐/tri‐atomic Fe centers with engineered S/N coordination. Theoretical calculation reveals that proper Fe gathering and coordination modulation could mildly delocalize the electron distribution and optimize the free energy pathways of ORR. In addition, the triple doping and hollow structure of carbon matrix could further regulate the local environment and allow sufficient exposure of active sites, resulting in more enhanced ORR kinetics on FeACs/NPS−HC. The zinc‐air battery assembled with FeACs/NPS−HC as cathodic catalyst exhibits all‐round superiority to Pt/C and most Fe‐based ADCs. This work provides an exemplary method for establishing atomic‐cluster catalysts with engineered S‐dominated coordination and hollowed carbon matrix, which paves a new avenue for the fabrication and optimization of advanced ADCs. [ABSTRACT FROM AUTHOR]

MXene is an emerging 2D material and shows large potential as a substrate for in situ growth of functional materials due to its merits such as large surface area, abundant nucleation sites, structural diversity, superior dispersion ability, blocking agglomeration of nanomaterials, and rich element/kind compositions. The in situ‐formed MXene‐based composites are largely applied in rechargeable batteries in the past several years by acting as active materials, serving as current collectors, decorating separators, and catalyzing electrochemical process. However, a detailed and systematic summary is still lacked. Herein, a review on in situ growth engineering on 2D MXene for next‐generation rechargeable batteries is presented in detail for the first time. Meanwhile, some outlooks and perspectives are put forward. In situ growth engineering on 2D MXenes can be achieved by calcination method, hydrothermal method, solvothermal method, room‐temperature liquid‐phase reduction method, room‐temperature liquid‐phase oxidation method, electrochemical deposition method, in situ polymerization method, vapor deposition method, mechanical milling method, microwave method, composite method, self‐reduction method, coprecipitation method, immersion method, hydrolysis method, etc. These in situ growth strategies can be extended to materials beyond MXenes, such as graphene, MBene, graphdiyne, etc. [ABSTRACT FROM AUTHOR]

Achieving aqueous zinc‐ion batteries (AZIBs) with high capacity and long lifetime remains challenging because the intense charge repulsion of multivalent ions causes structural instability and sluggish kinetics. The electrochemical activity brought by in situ structure optimization has dramatically improved the electrochemical performance. Hereinto, the nanocomposites consisting of VN/V2O3 heterostructure composited with carbon (VN/V2O3@C) by a self‐template strategy are synthesized. The VN/V2O3 heterostructure undergoes an in situ electrochemical activation phase transition to highly reversible V2NO after the first cycle. The interface of V2O3 and VN induces ion displacement polarization under the action of the applied electric field, making it easier for oxygen and nitrogen atoms to dope into the crystal structure of VN and V2O3, contributing to V2NO phase formation. Furthermore, theory calculations demonstrate that V2NO can provide favorable adsorption for reversible Zn2+ storage. The V2NO@C electrode thus delivers high reversible capacities of 490.2 mAh g−1 after 310 cycles at 200 mA g−1 and impressive long‐cycle stability over 6000 cycles at 10 A g−1. Herein, it sheds new light on the mechanism of in situ electrochemical phase transition from heterostructures into one phase, which is a great revolution in designing cathode materials for AZIBs. [ABSTRACT FROM AUTHOR]

Aqueous Zn−ion batteries (AZIBs) promise appealing advantages including safety, affordability, and high volumetric energy density. However, rampant parasitic reactions and dendrite growth result in inadequate Zn reversibility. Here, a biocompatible additive, L‐asparagine (Asp), in a low‐cost aqueous electrolyte, is introduced to address these concerns. Combining substantive verification tests and theoretical calculations, it is demonstrated that an Asp‐containing ZnSO4 electrolyte can create a robust nanostructured solid‐electrolyte interface (SEI) by simultaneously modulating the Zn2+ solvation structure and optimizing the metal‐molecule interface, which enables dense Zn deposition. The optimized electrolyte supports excellent Zn reversibility by achieving dendrite‐free Zn plating/stripping over 240 h at a high Zn utilization of 85.5% in the symmetrical cell and an average 99.6% Coulombic efficiency for over 1600 cycles in the asymmetrical cell. Adequate full‐cell performance is demonstrated with a poly(3,4‐ethylenedioxythiophene) intercalated vanadium oxide (PEDOT‐V2O5) cathode, which delivers a high areal capacity of 4.62 mAh cm−2 and holds 84.4% capacity retention over 200 cycles under practical conditions with an ultrathin Zn anode (20 µm) and a low negative/positive capacity ratio (≈2.4). This electrolyte engineering strategy provides new insights into regulating the anode/electrolyte interfacial chemistries toward high‐performance AZIBs. [ABSTRACT FROM AUTHOR]

Continuous and considerable exploration of two–dimensional transition metal carbides and nitrides (MXenes)toward interlayer spacing expansion, surface termination modification and composition architecture construction has aroused significant interest in energy storage fields. Nevertheless, their employment remains severely impeded by a fundamental lack of comprehension of the coordination chemistry of MXenes. Herein, hierarchical porous N‐doped carbon encapsulated fluorine‐free Ti3C2Tx with tunable coordination chemistry is fabricated by a novel one‐pot etching strategy. The Ti coordinated with N manipulated by phase reconstruction is identified by high‐angle annular dark‐field scanning transmission electron microscopy and X‐ray photoelectron spectroscopy. Moreover, hierarchical porous nitrogen‐doped carbons (HPNC) are distinctly observed that result in a multifold increase in material surface area derived from a substantial increment of micro‐ and mesoporosity. The structural synergistic effect of Ti coordinated with N, and HPNC heighten binding energy and reduce energy barriers that accelerate redox kinetics, and boosts physical immobilization of lithium polysulfides. The aforementioned MXenes modified separators endow lithium–sulfur batteries with a reversible capacity of 889.5 mA h g−1 with capacity retention of 79.5% after 100 cycles at 0.5 A g−1. Overall, this work affords a novel and universal etching strategy in terms of directly synthesizing fluoride‐free MXene with tunable coordination chemistry toward exploring the correlation between structural and electrochemical properties. [ABSTRACT FROM AUTHOR]

Bio‐organisms with various architectures and versatile physiological functions provide a substantial bibliography for electrode design. To elucidate how bio‐organisms and bio‐schemes take effect in advanced electrode materials, this review sorts bio‐assisted construction into two categories, namely, biotemplating synthesis and biomimetic artificial fabrication. The former section summarizes unique characteristics of different biotemplates for electrode preparation, including "bottom‐up" structural designability of biomolecules, metabolism involving, and genetic alterable properties of biological cells, as well as, the structural regularity and integrity of bio‐tissues, with the aim to provide guidelines for manipulating bioarchitectures and endow biotemplating synthesis of electrodes with more designability. The later describes recent efforts in using bio‐prototypes to enhance the essential properties associated with advanced electrodes, including mechanical properties, wettability, mass transport, electron/charge transfer, and catalytic activity, with intensive concerns on the function principles of biomimetic designs in electrochemical systems. Then, advances in applications of bioderived and biomimetic electrode materials are summarized emphasizing how bio‐structures/components and bionic designs help to enhance the charging/discharging and electrocatalytic performance in specific electrochemical energy storage and conversion systems. Finally, future trends with prospects and challenges for developing new bioderived/biomimetic electrode materials, as well as, related conceptual innovation on bionics, are discussed in the last section. [ABSTRACT FROM AUTHOR]

The practical application of lithium‐sulfur (Li−S) batteries is greatly hindered by the shuttle effect of dissolved polysulfides in the sulfur cathode and the severe dendritic growth in the lithium anode. Adopting one type of effective host with dual‐functions including both inhibiting polysulfide dissolution and regulating Li plating/stripping, is recently an emerging research highlight in Li−S battery. This review focuses on such dual‐functional hosts and systematically summarizes the recent research progress and application scenarios. Firstly, this review briefly describes the stubborn issues in Li−S battery operations and the sophisticated counter measurements over the challenges by dual‐functional behaviors. Then, the latest advances on dual‐functional hosts for both cathode and anode in Li−S full cells are catalogued as species, including metal chalcogenides, metal carbides, metal nitrides, heterostuctures, and the possible mechanisms during the process. Besides, we also outlined the theoretical calculation tools for the dual‐functional host based on the first principles. Finally, several sound perspectives are also rationally proposed for fundamental research and practical development as guidelines. [ABSTRACT FROM AUTHOR]

Exploring a general method for synthesizing 2D compounds with high accessible surface area and nano‐thickness as advanced electrocatalysts is essential yet challenging. Herein, a self‐assembly induced reverse micelle templating method followed by topochemical transformation is developed to synthesize a series of cobalt‐based compounds with varied anions and similar ultrathin 2D structures. Electrocatalytic behaviors for the hydrogen evolution reaction (HER) are systematically investigated, which demonstrate enhanced performances of ultrathin 2D compounds than their agglomerated counterparts. Among them, 2D CoP is particularly prominent. The overpotential of 144 mV at 10 mA cm−2, together with superb stability, place it among the best single‐phase phosphide HER catalysts reported thus far. Theoretical calculation and experimental results demonstrate the favorable valence electronic structure with moderate hydrogen adsorbability and good intracrystalline conductivity, as well as the homogeneous ultrathin 2D configuration with sufficiently exposed active sites and shortened intracrystalline electron transport route, are the dominant reasons that 2D CoP exhibits optimal electrocatalytic activity for HER. This study presents a novel and extendable strategy for synthesizing various 2D metal‐based compounds with valuable insights into the modulation essence of advanced electrocatalysts. [ABSTRACT FROM AUTHOR]

Aqueous zinc–ion batteries (ZIBs) have been promptly developed as a competitive and promising system for future large‐scale energy storage. In recent years, vanadium (V)‐based compounds, with diversity of valences and high electrochemical‐activity, have been widely studied as cathodes for aqueous ZIBs because of their rich reserves and high theoretical capacity. However, the stubborn issues including low conductivity and sluggish kinetics, plague their smooth application in aqueous ZIBs. Among various countermeasures, defect engineering is believed as an effective method to alleviate the above limitations. This review highlights the challenges of different V‐based cathode materials (e.g., vanadium oxides and vanadates) and summarizes the advances in defect engineering strategies including types and effects of the defects, designed strategies, and characterization techniques for high‐energy ZIBs. Finally, several sound prospects in this fervent field are also rationally proposed for fundamental research and practical application. [ABSTRACT FROM AUTHOR]

The catalytic activity of main‐group metal is hard to promote because of the intrinsic lack of host d orbitals available to be combined. Herein, under the guidance of theoretical predictions, we find atom‐dispersed antimony sites (Sb−N4 moieties) can be activated to achieve high oxygen reduction reaction (ORR) activity using a functional group regulation strategy. Correspondingly, we manage to synthesize a main‐group Sb single‐atom catalysts (SACs) that comprises Sb−N4 active moieties functionalized by epoxy groups in the second microenvironment and incorporated in N‐doped graphene (Sb1/NG(O)). The electron‐rich epoxy group can adjust the electronic structure of Sb−N4 active moieties, thereby optimizing the adsorption of the intermediate. The Sb SACs are comparable to industrial Pt/C under alkaline conditions. This discovery provides new opportunities to manipulate and improve the catalytic activity of main‐group‐element electrocatalysts. [ABSTRACT FROM AUTHOR]

Siloxene as a new type of 2D material has wide potential applications due to its special structure. Especially, as anode for lithium‐ion batteries, siloxene shows promising prospect due to its small volume change and low diffusion pathway. However, the unstable solid electrolyte interphase and low electronic conductivity lead to the low Coulombic efficiency, poor rate capability, and limited cycling performance. To settle the problems, a thin porous covalent organic framework (COF) coating layer is designed by in situ growth on micro‐sized siloxene. With the inherent ionic conductive and electrolyte compatible advantages of COF, the engineered siloxene demonstrates superior electrochemical performance with 96% capacity retention at 8 A g−1 for 1500 cycles. [ABSTRACT FROM AUTHOR]

Herein, NbN nanocrystals immobilized on N‐doped carbon nanosheets to functionalize a polypropylene (PP) membrane (NbN@NC/PP) with a thin coating of only 4 µm are designed and synthesized. The functional modifier layer allows for sulfur‐involved transformations and also lithium plating behaviors. On the one hand, the sulfur cell with NbN@NC/PP separator exhibits excellent cycling stability and rate capacity. The good electrochemical performance partially results from the strong chemical interactions between NbN and lithium polysulfides via the formation of NbS and NLi bonds, which is proven by the first‐principles calculations and X‐ray photoelectron spectroscopy analyses. The formation of tiny nanoscrystals (<2 nm) and clusters tends to maximize the surface of NbN to interact with polysulfides and enable the effective catalysis over the sulfur‐involved reactions. The higher exchange current density and Li+ diffusion coefficient of NbN@NC/PP cells experimentally verify that the introduction of NbN indeed catalytically accelerates the reaction kinetics. On the other hand, the performance of Li//Li symmetric cells demonstrates that the NbN@NC modifier layer can well induce homogeneous lithium deposition. This work confirms the application potential of NbN in lithium–sulfur batteries and encourages the exploration of prospective nitrides to engineer high performance next‐generation batteries. [ABSTRACT FROM AUTHOR]

The practical application of lithium–sulfur batteries is still limited by the lithium polysulfides (LiPSs) shuttling effect on the S cathode and uncontrollable Li‐dendrite growth on the Li anode. Herein, elaborately designed WSe2 flakelets immobilized on N‐doped graphene (WSe2/NG) with abundant active sites are employed to be a dual‐functional host for satisfying both the S cathode and Li anode synchronously. On the S cathode, the WSe2/NG with a strong interaction towards LiPSs can act as a redox accelerator to promote the bidirectional conversion of LiPSs. On the Li anode, the WSe2/NG with excellent lithiophilic features can regulate the uniform Li plating/stripping to mitigate the growth of Li dendrite. Taking advantage of these merits, the assembled Li−S full batteries exhibit remarkable rate performance and stable cycling stability even at a higher sulfur loading of 10.5 mg cm−2 with a negative to positive electrode capacity (N/P) ratio of 1.4 : 1. [ABSTRACT FROM AUTHOR]

A new type of anode material in which small‐sized CoP nanoparticles coated with N‐doped carbon are immobilized into 1D nitrogen‐doped carbon frameworks (CoP@NC⊂NCFs) is accurately synthesized via self‐template catalysis. The hierarchical structure bears various structural advantages, including more active sites and ultrahigh electrical conductivity provided by enriched nitrogen, strong interface interaction between CoP and N‐doped carbon, and the stability of the structure. As a result, the rapid potassium ion reaction kinetics and the strong adsorption of potassium ions of CoP are realized, verified by galvanostatic intermittent titration and density function theory calculations. In addition, through the advanced in situ characterization techniques, the solid‐solution reaction mechanism of CoP and potassium ions is clarified. The zero‐strain structure of CoP further ensures structural robustness, giving CoP@NC⊂NCFs excellent potassium storage properties, especially cycle stability with a capacity of ≈206 mAh g−1 at 0.1 A g−1 for 1200 cycles, achieving an ultralow decay rate of 0.01%. The corresponding K‐ion full cell is also prepared, as expected, and shows stable capacity retention. [ABSTRACT FROM AUTHOR]

Ionically conductive polymers are a promising family of electrolytes for electrochemical devices, including batteries, and flexible electronics. The polymer electrolytes with an excellent mechanical property probably can inhibit the dendrites growth during charging/discharging. Herein, the mechanical properties of an N−methyl−N−propyl piperidinium bis(trifluoromethanesulfonyl)imide/poly(vinylidene fluoride‐hexafluoropropylene) gel polymer electrolyte is improved through compositing with %TiO2 nanoparticles. The gel polymer electrolyte shows increased loss modulus after compositing with 5 wt% TiO2, indicating that the inorganic nanoparticles can increase the viscous response of polymer electrolytes. The Li‐ion conductivity shows a noticeable dependence on %TiO2 and the highest ionic conductivity is obtained at 5 wt% TiO2. The presence of TiO2 in the gel polymer electrolyte also allows for smaller interfacial resistance and a more stable Li−electrolyte interface upon long‐term storage and battery cycling. As a result, when assembled with the LiFePO4 and LiNi0.6Mn0.2Co0.2O2 cathodes, the composite gel polymer electrolyte improves the full‐cell performance, such as higher Coulombic efficiency, improved cycling stability, and more stable electrode–electrolyte interface. [ABSTRACT FROM AUTHOR]

What has been a crucial demand is that designing mighty cathode materials for aqueous zinc−ion batteries (AZIBs), which are vigorous alternative devices for large−scale energy storage by means of their high safety and low cost. Herein, a facile strategy is designed that combines oxygen defect engineering with polymer coating in a synergistic action. As an example, the oxygen−deficient hydrate vanadium dioxide with polypyrrole coating (Od−HVO@PPy) is synthesized via a one‐step hydrothermal method in which introducing oxygen vacancy in HVO is simultaneously realized during the in situ polymerization. Such a desirable material adjusts the surface adsorption and internal diffusion of Zn2+ demonstrated by electrochemical characterization and theoretical calculation results. Moreover, it also utilizes conductive polymer coating to improve electrical conductivity and suppress cathode dissolution. Therefore, the Od−HVO@PPy electrode delivers a preferable reversible capacity (337 mAh g−1 at 0.2 A g−1) with an impressive energy density of 228 Wh kg−1 and stable long cycle life. This enlightened design opens up a new modus operandi toward superior cathode materials for advanced AZIBs. [ABSTRACT FROM AUTHOR]

Use of catalytic materials is regarded as the most desirable strategy to cope with sluggish kinetics of lithium polysulfides (LiPSs) transformation and severe shuttle effect in lithium–sulfur batteries (LSBs). Single‐atom catalysts (SACs) with 100 % atom‐utilization are advantagous in serving as anchoring and electrocatalytic centers for LiPSs. Herein, a novel kind of tungsten (W) SAC immobilized on nitrogen‐doped graphene (W/NG) with a unique W‐O2N2‐C coordination configuration and a high W loading of 8.6 wt % is proposed by a self‐template and self‐reduction strategy. The local coordination environment of W atom endows the W/NG with elevated LiPSs adsorption ability and catalytic activity. LSBs equipped with W/NG modified separator manifest greatly improved electrochemical performances with high cycling stability over 1000 cycles and ultrahigh rate capability. It indicates high areal capacity of 6.24 mAh cm−2 with robust cycling life at a high sulfur mass loading of 8.3 mg cm−2. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium‐ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol‐gel synthesis followed by molten salt carbonization route to fabricate graphene‐like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D‐C). The in‐situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as‐obtained SiOx/C@2D‐C delivers a discharge capacity of 559 mAh·g−1 at 0.5 A·g−1 after 200 cycles and 548 mAh·g–1 at 1.0 A·g−1 even after 1000 cycles. The full cell assembled with SiOx/C@2D‐C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh·kg−1 and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx‐based materials for high energy LIBs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) with a high theoretical capacity of 1675 mAh g−1 hold promise in the realm of high‐energy‐density Li–metal batteries. To cope with the shuttle effect and sluggish transformation of soluble lithium polysulfides (LiPSs), varieties of traditional metal‐based materials (such as metal, metal oxides, metal sulfides, metal nitrides, and metal carbides) with unique catalytic activity for accelerating LiPSs redox have been exploited to fundamentally inhibit the shuttle effect and improve the performance of LSBs. Concurrently, some budding catalytic materials also possess enormous potential for facilitating LiPSs redox reaction in LSBs, including metal borides, metal phosphides, metal selenides, single atoms, and defect‐engineered materials. Here, recent advances in these emerging catalytic candidates as well as the evaluation methods and parameters for catalytic materials are comprehensively summarized for the first time. New insights are also given to aid in the design of high‐performance LSBs and satisfy the high expectation in the future, including the exposure of the active sites and adsorption‐catalysis synergy strategies. Finally, the current challenges and prospects for designing highly efficient catalytic materials are highlighted, aiming at providing guidance for configuring catalytic materials to make sure high‐energy and long‐life LSBs. [ABSTRACT FROM AUTHOR]

In the past decades, the world has witnessed the successful commercialization of "rocking‐chair"‐type lithium‐ion batteries with lithium metal free anodes. Owing to their safe, green, easy manufacturing, and cost‐efficiency characteristics, rechargeable zinc batteries have recently received more and more attention. However, the practical application of Zn metal batteries is hampered mainly by the dendritic growth of Zn metal anode, which leads to poor Coulombic efficiency, hazards, and various side reactions. Herein, the emerging "rocking‐chair"‐type Zn‐ion batteries are systemically reviewed with Zn host anodes instead of Zn metal anodes. As an introduction, the fundamental principles, advantages, and challenges of "rocking‐chair"‐type Zn‐ion batteries are discussed. Subsequently, the design principles and recent advances of cathode, anode, and electrolyte for "rocking‐chair" Zn‐ion batteries are summarized. To conclude, perspectives on the future of "rocking‐chair" Zn‐ion batteries are presented. It is hoped that this review may provide alternative directions for the design of Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

Hybrid hierarchical micro/nanostructures possess great potential in engineering of advanced electrode materials for sodium‐ion batteries (SIBs). Herein, a sandwich hierarchical architecture composed of ZnSe nanoparticles fastened in N‐doped carbon polyhedra anchoring onto graphene with the modification of MoSe2 nanosheets (ZnSe⊂N‐C@MoSe2/rGO) is synthesized by a self‐template and subsequent selenization strategy. Due to the distinctive architectural and multicompositional features, these hybrids deliver a high reversible capacity of 319.4 mAh g−1 at 1 A g−1 for 1800 cycles, 206.5 mA h g−1 at 6 A g−1 for 2800 cycles, and 177.7 mAh g−1 at 10 A g−1 for 5000 cycles, as well as a better rate capability up to 10 A g−1 with a reversible capacity of 224.4 mAh g−1 as an anode material for SIBs. By comparing the capacity contribution, electrochemical impedance spectra and DNa+ of different materials, the advantages of ZnSe⊂N‐C@MoSe2/rGO are confirmed. The sodium storage mechanism of hybrids is further revealed by in situ X‐ray diffraction patterns and high‐resolution transmission electron microscopy results. The improved sodium storage properties of hybrids manifest the significance of elaborate construction of novel multicomponent hierarchical architectures with higher complexity. [ABSTRACT FROM AUTHOR]

In spite of the valuable advancements in the fabrication of transition‐metal selenides (TMSs)‐based hybrid structures, only single‐metal selenides have been obtained through most of the present methods. Herein, a facile room‐temperature self‐polymerization and subsequent selenization strategy is proposed for the synthesis of bimetallic MoxW1−xSe2 nanosheets with expanded interlayers decorated with N‐doped carbon‐matrix assembled flowerlike hierarchical microspheres (MoxW1−xSe2/NC). Depending on the excellent coordination ability of dopamine with metal ions, self‐formed flowerlike single precursors are harvested. The unique hybrid architecture benefits the penetration of the electrolyte, accelerates Na+ insertion/extraction kinetics, enhances electron‐transfer ability, and alleviates the volume expansion and aggregation during cycling processes. Therefore, the bimetallic MoxW1−xSe2/NC electrode delivers high reversible capacities of 264 mA h g−1 at 1 A g−1 for 700 cycles, 204.4 mA h g−1 at 4 A g−1 for 1400 cycles, and 153.3 mA h g−1 at 8 A g−1 for 2000 cycles, as well as an excellent rate capability up to 10 A g−1 with a capacity of 188.9 mA h g−1. Our study offers an effective strategy to boost sodium storage performance through elaborate structural engineering. [ABSTRACT FROM AUTHOR]

Transition‐metal phosphides (TMPs)‐based electrode materials with high capacity have attracted considerable interest as a promising anode material for lithium−ion batteries (LIBs). Herein, a hierarchical cable‐like structure composed of CoP@C core−shell nanoparticles (NPs) encapsulated in one‐dimensional (1D) porous carbon framework intertwined with N‐doped carbon nanotubes (CoP@C⊂PCF/NCNTs) is synthesized by a self‐templating, self‐catalytic, and subsequent vapor‐phase phosphorization strategy. The unique nanoarchitecture regime provides multiple advantages. The 1D carbon framework allows for quick ion and electron access, maintaining the integrity and accommodating the volume change of the structure during repeated discharging/charging. The internal carbon shell can prevent the direct aggregation of CoP NPs on cycling. The external NCNTs on the surface supply a staggered conductive network to promote electrolyte penetration and charge transportation. Impressively, the as‐fabricated hybrid nanocables deliver a reversible capacity of 712 mAh g−1 at 0.5 A g−1 for over 700 cycles with excellent rate capability as an anode material for LIBs. The significantly improved lithium storage properties of CoP@C⊂PCF/NCNTs reveal the importance of reasonable design and engineering of novel hierarchical structures with higher complexity. [ABSTRACT FROM AUTHOR]