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The practical application of Li‐rich Mn‐based oxide cathode is predominately retarded by the capacity decline and voltage fading, associated with the structure distortion and anionic redox reactions. Here, a linkage‐functionalized modification approach to tackle these challenges via a synchronous lithium oxidation strategy is reported. The doping of Ce in the bulk phase activates the pseudo‐bonding effect, effectively stabilizing the lattice oxygen evolution and suppressing the structure distortion. Interestingly, it also induces the formation of spinel phase Li4Mn5O12 in the subsurface, which in turn constructs the phase boundaries, thereby arousing the interior self‐built‐in electric field to prevent the outward migration of bulk oxygen anions and boost the charge transfer. Moreover, the formed coating layer Li2CeO3 with oxygen vacancies accelerates Li+ diffusion and mitigates electrolyte cauterization. The corresponding cathode exhibits superior long‐cycle stability after 300 cycles with only a 0.013% capacity drop and 1.76 mV voltage decay per cycle. This work sheds new light on the development of Li‐rich Mn‐based oxide cathodes toward high energy density applications. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical nanoscale carbons have received wide interest as electrode materials for energy storage and conversion due to their fast mass transfer processes, outstanding electronic conductivity, and high stability. Here, heteroatom (S, P, and N) doped hierarchical vesicular carbon (HHVC) materials with a high surface area up to 867.5 m2 g−1 are successfully prepared using a surface polymerization of hexachloro‐cyclotriphosphazene (HCCP) and 4,4′‐sulfonyldiphenol (BPS) on the ZIF‐8 polyhedrons. Significantly, it is the first time to achieve a controllability of the wall thickness for this unique carbon, ranging from 18 to 52 nm. When utilized as anodes for sodium ion batteries, these novel carbon materials exhibit a high specific capacity of 327.2 mAh g−1 at 100 mA g−1 after 100 cycles, which can be attributed to the expanded interlayer distance and enhanced conductivity derived from the doping of heteroatoms. Importantly, a high capacity of 142.6 mAh g−1 can be obtained even at a high current density of 5 A g−1, assigning to fast ion/electronic transmission processes stemming from the unique hierarchical vesicular structure. This work offers a new route for the fabrication/preparation of multi‐heteroatom doped hierarchical vesicular materials. [ABSTRACT FROM AUTHOR]

As an anode material for sodium-ion batteries (SIBs), antimony (Sb) has attracted significant interest due to its high theoretical specific capacity. However, it suffers from a huge volume change during the sodiation–desodiation process that leads to poor cyclability. Herein, cross-linked carbon nanosheet frameworks (CCNFs) and Sb nanoparticles (NPs) were combined to construct a high-performance anode material for SIBs. In this composite, Sb nanoparticles were tightly anchored on the carbon frameworks; this provided enhanced structural stability to Sb and prevented the agglomeration during the charge–discharge process. Sb provides a high specific capacity, and the carbon frameworks ensure structural integrity and conductive networks. Moreover, due to this synergistic effect, the as-prepared Sb/CCNFs composite exhibits an excellent cycle stability and rate performances. Considering both the capacity and rate property, the overall performances of the obtained Sb/CCNFs reach the highest level in comparison with those of the reported Sb/C composites. The reversible (charge) capacity can remain 549.3 mA h g−1 after 100 cycles at a current density of 100 mA g−1. Moreover, a superior rate performance is observed as the reversible capacity still reaches 318 mA h g−1 at a high current density of 3200 mA g−1. Therefore, this study proposes an effective methodology to improve the key performances of the SIB anode. [ABSTRACT FROM AUTHOR]

The conventional strategies for obtaining S/N-codoped carbon materials suffer from a series of problems caused by their complicated experimental procedures. Here, S,N-codoped carbon nanosheets were firstly prepared by a solvent-free one-pot method, displaying an ultra-thin sheet-like structure, a tunable interlayer distance ranging from 0.37 nm to 0.41 nm, and a large surface area up to 809 m2 g−1. When they were used as an anode for sodium-ion batteries (SIBs), an outstanding sodium-ion storage performance of 380 mA h g−1 was acquired at 100 mA g−1, which can be attributed to the expanded interlayer distance caused by the introduction of the large covalent radius-sulfur. The initial coulombic efficiency improved to 60.9%, which may benefit from N-doping. Most importantly, an excellent rate capability of ∼178 mA h g−1 was observed at a current density of 5 A g−1 after 5000 cycles, which is among best of the state-of-the-art carbon-based SIBs. Interestingly, the morphology of the obtained carbon materials can be tuned from bulk to flake by adjusting the sulfur content or temperature. Given this, this work provides a new method to construct co-doped carbon (especially tri-doped and multi-doped carbon) and shows that the strategy of co-doping of heteroatoms can effectively optimize the nano/microstructure and enhance the rate capability of the carbon materials. [ABSTRACT FROM AUTHOR]

Carbon materials have been widely applied in the energy storage devices, however, the preparation of suitable carbon materials for sodium-ion batteries (SIBs) is still a challenge. In this paper, N-doped porous carbon material (NDPCs) with rose-like structure has been successfully prapared through pyrolysis of the as-prepared polyimides in-situ. The NDPCs shows rose-like structure derived from 2D nanosheets, an expanded interlayer distance of 0.387 nm, a high specific surface area of 215.7 m 2 g −1 and the electrochemical performances for Na-ion batteries are systematically investigated. A high reversible specific capacity of 240 mAh g −1 at a current density of 100 mA g −1 is attained and a specific capacity of 224 mAh g −1 is remained even after 100 cycles. Remarkably, even at a high current density of 3.2 A g −1 , the reversible specific capacity of 104 mAh g −1 can be observed. This excellent performance of NDPCs electrode may be ascribed to its superior structure, since the micropore/mesopore might efficiently shorten the diffusion distance of Na-ion and the enlarged interlayer spacing of 0.38 nm is significant for Na-ion insertion/extraction. Significantly, the approach to prepare carbon materials from PI may be generalized to other polymers. [ABSTRACT FROM AUTHOR]

Carbon-coated rutile titanium dioxide (CRT) was fabricated through an in-situ pyrolysis of titanium-based metal organic framework (Ti 8 O 8 (OH) 4 [O 2 CC 6 H 4 CO 2 ] 6 ) crystals. Benefiting from the Ti O C skeleton structure of titanium-based metal organic framework, the CRT possesses abundant channels and micro/mesopores with the diameters ranging from 1.06 to 4.14 nm, shows larger specific surface area (245 m 2 g −1 ) and better electronic conductivity compared with pure titanium dioxide (12.8 m 2 g −1 ). When applied as anode material for sodium-ion batteries, the CRT electrode exhibits a high cycling performance with a reversible capacity of ∼175 mAh g −1 at 0.5 C-rate after 200 cycles, and obtains an excellent rate capability of ∼70 mAh g −1 after 2000 cycles even at a specific current of 3360 mA g −1 (20 C-rate). The outstanding rate capability can be attributed to the carbon-coated structure, which may effectively prevent aggregation of the titanium dioxide nanoparticles, accelerate the mass transfer of Na + and speed up the charge transfer rate. Considering these advantages of this particular framework structure, the CRT can serve as an alternative anode material for the industrial application of SIBs. [ABSTRACT FROM AUTHOR]

Cube-shaped porous carbon (CPC) was obtained from the carbonization of MOF-5 (Zn 4 O(OOCC 6 H 4 COO) 3 ) crystals and shows abundant micro/mesopores, high mechanical strength, largest surface area (2316 m 2 g −1 , BET method) and good electrical conductivity (a high weight ratio 98.17/1.83 of C/O). When utilized as anode material for sodium-ion batteries, the CPC presents a high overall sodium storage capacity ∼240 mAh g −1 at a current density of 100 mA g −1 after 100 cycles, and maintains a high specific capacity of 100 mAh g −1 after 5000 cycles at a current density of 3200 mA g −1 . For the advantages of this unique carbon framework structure, the CPC might be a promising anode material for the application of SIBs. [ABSTRACT FROM AUTHOR]

A facile route to improve the lithium-storage properties of flake graphite (FG) is proposed through coating pyrolysis carbon from polyvinylidene fluoride (PVDF) assisted by KOH activation. The interplanar distance between the graphene sheets of activated PVDF/FG is enlarged, effectively suppressing the electrode deformation during lithium (de)-intercalation. More edge and porous structures of PVDF/FG arising from KOH activation on graphite flakes contribute to improved electron and ion transport, leading to great improvement in its rate and cycling performances. The initial specific capacity of the activated PVDF/FG is 476.6 mAh g −1 at 50 mA g −1 and when the current increases to 1000 mA g −1 , the value still retains 142.6 mAh g −1 . [ABSTRACT FROM AUTHOR]

A novel hollow-structured Mn/TS-1 catalyst has been reported as a non-nitric acid route for adipic acid production from oxidative cleavage of cyclohexanone. The method generates adipic acid in high yields with molecular oxygen under organic solvent- and promoter-free conditions. The hollow nature of the catalyst with large intra-particle voids facilitates the diffusion of bulky molecules to the internal catalytic site and increases the catalyst activity. The advantage of this catalyst is its reusability with almost consistent reactivity, thereby making it viable for industrial applications. [ABSTRACT FROM AUTHOR]

One-step oxidation of cyclohexane to adipic acid (AA) was carried out at 413 K over manganese-doped titanium silicalite with hollow structure (HTS) using oxygen as oxidant without any initiator or solvent. The catalyst exhibited high conversion (13.4%) and reasonable product (AA) selectivity (57.5%). Hot-separation and catalyst-recycle tests proved that the catalyst acted as a heterogeneous one and it could be reused four times without losing its activity. The synthesized materials were characterized by N 2 adsorption–desorption isotherm, FT-IR, UV–vis and XPS techniques. [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]

[Display omitted] Na 4 Fe 3 (PO 4) 2 (P 2 O 7) (NFPP) is currently drawing increased attention as a sodium-ion batteries (SIBs) cathode due to the cost-effective and NASICON-type structure features. Owing to the sluggish electron and Na+ conductivities, however, its real implementation is impeded by the grievous capacity decay and inferior rate capability. Herein, multivalent cation substituted microporous Na 3.9 Fe 2.9 Al 0.1 (PO 4) 2 (P 2 O 7) (NFAPP) with wide operation-temperature is elaborately designed through regulating structure/interface coupled electron/ion transport. Greatly, the derived Na vacancy and charge rearrangement induced by trivalent Al3+ substitution lower the ions diffusion barriers, thereby endowing faster electron transport and Na+ mobility. More importantly, the existing Al—O—P bonds strengthen the local environment and alleviate the volume vibration during (de)sodiation, enabling highly reversible valence variation and structural evolution. As a result, remarkable cyclability (over 10,000 loops), ultrafast rate capability (200 C), and exceptional all-climate stability (−40–60 °C) in half/full cells are demonstrated. Given this, the rational work might provide an actionable strategy to promote the electrochemical property of NFPP, thus unveiling the great application prospect of sodium iron mixed phosphate materials. [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]

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]

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]

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]

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]

Carbon‐based supercapacitors are one of the most widely used commercial products. Organic electrolyte systems, such as tetraethylammonium tetrafluoroborate/acetonitrile (TEABF4/ACN), remain dominant after decades of development due to cost and performance advantages. However, improving the capacitance of existing carbon‐electrolyte systems not by altering the pore structure and surface properties of activated carbon is full of challenges. Herein, a non‐Faraday organic ferroelectric salt additive (diisopropylamine perchlorate, DIPAP) that can significantly increase capacitance from the standpoint of electrolyte dielectric modulation is proposed for the first time. Compared to counter ions, DIPA+ plays a vital role in capacity enhancement, in which electron‐rich N‐doped mesoporous carbon can greatly boost capacity by promoting local ion mobility. In situ Raman and theoretical studies show that small‐size DIPA+ can enter the pore and be enriched closer to electrode surfaces than TEA+ and ACN, allowing it to regulate the distribution of electric double‐layer species and dielectric properties (i.e., effective thickness of dielectric and/or relative dielectric constant), increasing capacity by up to 21.6–45.8% with only 1 wt% DIPAP while maintaining desired rate performances. The understanding of the mechanism of capacitance increase by such additives opens up new avenues for further extension of the commercialized carbon electrode‐organic electrolyte system's potential. [ABSTRACT FROM AUTHOR]

Aiming at the problems of poor cycle stability of carbon-based materials in potassium ion batteries, functionalized nitrogen and sulfur co-doped carbon dots (CDs) are applied to improve the potassium storage performance of electrode materials. In this work, the functionalized CDs are used to regulate the structure and morphology of the polypyrrole in-situ during the polymerization process of pyrrole monomer. Concretely, the original strip-like fibrous polypyrrole can be induced to become bead-like particle with the disappearance of fiber shape, and with the increase of the amount of carbon dots, the active particles increased. Compared with pure polypyrrole derived carbon, the carbon-dot-regulated polypyrrole derived carbon exhibits more excellent cycling performances with a shorter ion transmission and transfer path, more active sites, increased contact area with the electrolyte and improved structural stability. The specific capacity of the carbon anode carbonized from polypyrrole (C-ppy-NSCDs-100) regulated by 100 mg of carbon dots could reach 360.2 mAh g−1 at 0.1 A g−1, showing the application potential of carbon dots in improving electrochemical potassium storage by regulating the morphology of carbon-based materials. Predictably, these unparalleled features of CDs can be expected to inspire more exciting results in potassium-ion energy storage systems. • A series of polypyrrole carbon-based materials were obtained with the inducers of carbon dots. • The C-ppy-NSCDs-100 anode exhibited a specific capacity of 155.4 mAh g−1 at 1.0 A g−1 after 495 cycles. • The introduction of carbon quantum is an effective way to improve electrochemical potassium storage. [ABSTRACT FROM AUTHOR]

Designing Sb/carbon composite is an effective strategy to enhance the cycle stability and rate capability of Sb anodes for sodium ion batteries. However, the introduction of carbon often leads to a loss in specific capacity and initial Coulombic efficiency (ICE). In this work, a new perspective is adopted by focusing on improving the "sloping capacity" contribution of carbon (C) in Sb/C composites, rather than solely increasing the platform capacity of Sb as traditionally done. Theoretical predictions indicate that constructing Sb/C composites with high Sb and carbon interfacial areas can provide more Na adsorption sites, thus enhancing the "sloping capacity" of amorphous carbon. Guided by DFT, a rational Sb/C/NSCDs‐2(N) is successfully developed by self‐embedding Sb nanodots into 2D‐amorphous carbon sheets doped with N/S. Sb/C/NSCDs‐2(N) exhibits abundant Sb/carbon interfacial areas and excellent nanoscale effects, demonstrating ideal electrochemical sodium storage performances. Impressively, the Sb/C/NSCDs‐2(N) provides a "sloping capacity" close to 160 mAh g−1. Significantly, owing to the fact that these interfaces and defects are not in direct contact with the electrolyte, the side reaction of electrolyte is effectively inhibited, leading to no decrease of ICE. [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]

Developing electrode materials with high tap density, low cost, and superior performance poses a formidable challenge in electrochemistry. The impressive performance exhibited by most electrodes comes at the expense of tap density and cost, severely limiting their practical applications. Here, combining computational and experimental results, an approach for the electrode materials with high tap density and rich heterostructure (Cu2S/Na2Sn) from cheap copper smelting slag enabled by an electrochemical process is proposed, reducing the diffusion energy barrier from 0.82 to 0.28 eV for Na+, as well as delivering an impressively high tap density of 3.32 g cm−3. Furthermore, the electrochemical activation process that irreversibly generates more stable Cu2S and Na2Sn after the first charge progress of parent materials is also revealed by in/ex situ analytical techniques. As expected, assembled sodium ion capacitors (SICs) achieve high energy density (74.4 Wh kg−1) at high power density (20 000 W kg−1) with outstanding capacity retention of 81.5% after 10 000 cycles, delivering over 76% of its energy density in 13.4 s, which surpasses the performance achieved by state‐of‐the‐art SICs. This work not only provides novel insights into irreversibly conversion‐type anodes but also introduces a method for efficient value‐added utilization of smelting slag. [ABSTRACT FROM AUTHOR]

Sodium layered oxides feature in high capacity and diverse composition, however, are plagued by various issues including limited kinetics and interfacial instability with residual alkali. Conventional substitution/doping and heterogeneous coating are promising to tackle the problems of bulk and surface, respectively, but normally insufficient to address both. Herein, a post‐substitution strategy is proposed to modify primary sodium‐layered‐oxide particles that can simultaneously deal with bulk and surficial issues. As a typical example, post Ti‐substitution for O3‐NaNi1/3Fe1/3Mn1/3O2 is successfully performed by adjusting thermodynamic driving force, resulting in depth‐controllable Ti infusion from surface to bulk, as proved by energy dispersive spectroscopy maps collected at the cross‐section. Residual alkali species are efficiently diminished and benefited from the surface‐to‐bulk osmotic reaction, significantly improving Coulombic efficiency. Moreover, remarkable enhancements in reversible capacity (135 mAh g−1 at C/10), rate capability (74% retention at 5 C), and long‐term cycling stability (80% retention after 300 cycles at 2 C) are achieved by manipulating gradient‐like Ti distribution in a primary particle that brings with increased kinetics and strengthened interfacial stability, surpassing those given by rough heterotic coating and homogeneous Ti‐substitution. Such post‐substitution is expected to provide a universal strategy to modify primary layered‐oxide particles for developing advanced cathode materials of SIBs. [ABSTRACT FROM AUTHOR]

High‐voltage aqueous rechargeable energy storage devices with safety and high specific energy are hopeful candidates for the future energy storage system. However, the electrochemical stability window of aqueous electrolytes is a great challenge. Herein, inspired by density functional theory (DFT), polyethylene glycol (PEG) can interact strongly with water molecules, effectively reconstructing the hydrogen bond network. In addition, N, N‐dimethylformamide (DMF) can coordinate with Zn2+, assisting in the rapid desolvation of Zn2+ and stable plating/stripping process. Remarkably, by introducing PEG400 and DMF as co‐solvents into the electrolyte, a wide electrochemical window of 4.27 V can be achieved. The shift in spectra indicate the transformation in the number and strength of hydrogen bonds, verifying the reconstruction of hydrogen bond network, which can largely inhibit the activity of water molecule, according well with the molecular dynamics simulations (MD) and online electrochemical mass spectroscopy (OEMS). Based on this electrolyte, symmetric Zn cells survived up to 5000 h at 1 mA cm−2, and high voltage aqueous zinc ion supercapacitors assembled with Zn anode and activated carbon cathode achieved 800 cycles at 0.1 A g−1. This work provides a feasible approach for constructing high‐voltage alkali metal ion supercapacitors through reconstruction strategy of hydrogen bond network. [ABSTRACT FROM AUTHOR]

High‐voltage aqueous rechargeable energy storage devices with safety and high specific energy are hopeful candidates for the future energy storage system. However, the electrochemical stability window of aqueous electrolytes is a great challenge. Herein, inspired by density functional theory (DFT), polyethylene glycol (PEG) can interact strongly with water molecules, effectively reconstructing the hydrogen bond network. In addition, N, N‐dimethylformamide (DMF) can coordinate with Zn2+, assisting in the rapid desolvation of Zn2+ and stable plating/stripping process. Remarkably, by introducing PEG400 and DMF as co‐solvents into the electrolyte, a wide electrochemical window of 4.27 V can be achieved. The shift in spectra indicate the transformation in the number and strength of hydrogen bonds, verifying the reconstruction of hydrogen bond network, which can largely inhibit the activity of water molecule, according well with the molecular dynamics simulations (MD) and online electrochemical mass spectroscopy (OEMS). Based on this electrolyte, symmetric Zn cells survived up to 5000 h at 1 mA cm−2, and high voltage aqueous zinc ion supercapacitors assembled with Zn anode and activated carbon cathode achieved 800 cycles at 0.1 A g−1. This work provides a feasible approach for constructing high‐voltage alkali metal ion supercapacitors through reconstruction strategy of hydrogen bond network. [ABSTRACT FROM AUTHOR]

The difficulty in matching cathode and anode kinetics due to slow ion transport in anodes constrains the development of lithium‐ion capacitors. Heterogeneous structures with built‐in electric field can promote lithium‐ion migration and improve the anode reaction kinetics. However, the valence evolution of metal elements in heterostructures during charging/discharging processes is often overlooked. Inspired by theoretical calculations, transition metal selenides heterostructures (FeSe2/CoSe2) with low migration energy barriers (Eb = 0.35 eV) are successfully engineered and fabricated. As expected, the designed heterostructure material exhibits outstanding rate performance (512 mAh g−1 at 30 A g−1) and ultra‐high pseudocapacitance contribution (98.02% at 1.0 mV s−1), exceeding the state‐of‐the‐art values for anodes. Impressively, synchrotron X‐ray absorption spectroscopy (SXAS) and ex situ XPS find that the valence states of the Fe and Co elements in the heterogeneous structure gradually increase as charging and discharging proceeds, inducing a continuous climb in reversible specific capacity, while further reducing the migration energy barrier in the heterogeneous structure (Eb = 0.20 eV). This work reveals that the valence states of iron and cobalt elements increase as charging and discharging proceeds, providing theoretical guidance for improving the anode kinetics and revealing the capacity rise mechanism of other transition metal compounds. [ABSTRACT FROM AUTHOR]

Aqueous zinc anode has been re‐evaluated due to the superiority in tackling safety and cost concerns. However, the limited lifespan originating from Zn dendritic and side reactions largely hamper commercial development. Currently, the coating prepared by simple slurry mixing is leaky and ineffectively isolate sulfate and water. Herein, inspired by the DFT calculations and the easy hydrolysis characteristic of MIL‐125 (Ti), an in‐situ grown high‐dense TiO2‐x solid electrolyte interphase (HDSEI) with rich oxygen vacancies is successfully constructed in an aqueous electrolyte, in which the oxygen vacancies not only strengthen the hydrogen binding force thereby inhibiting the hydrogen precipitation by‐reaction, but also reduce the migration energy barrier of zinc ions and enhance the mechanical properties. Profiting from the HDSEI, symmetric Zn cells survive up to remarkable 4200 h at 1 mA cm−2, nearly 42‐times than that of bare Zn anodes. In situ optical microscopy clearly reveals that the in situ grown HDSEI homogenizes the zinc deposition process, while bare zinc without HDSEI shows significant dendrites, confirming the protective nature of HDSEI. Furthermore, full Zn ion capacitors can deliver excellent electrochemical performance, providing a feasible in situ approach to construct HDSEI to implement dendrite‐free metal anodes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The severe dendrite growth on zinc anode in alkaline electrolyte brings great challenge to the development of zinc‐based batteries. It is a simple and effective strategy to inhibit zinc dendrite formation by introducing additives into the electrolyte. In this study, N, S‐doped carbon dots (TU‐CQDs) were synthesized and used as additives to regulate zinc deposition in a typical KOH electrolyte. The experimental and three‐dimensional transient nucleation model disclosed that the special functional groups of carbon dots can change the electrode surface state and the coordination behaviors of zinc species in the electrolyte. Therefore, TU‐CQDs can not only inhibit the hydrogen evolution reaction, but also achieve uniform zinc deposition. The in‐situ synchrotron radiation X‐ray imaging elucidated that TU‐CQDs can effectively inhibit the dendrite growth and improve the reversibility of zinc plating/stripping process. This work provides a feasible route for regulating the reversibility of zinc metal anode in alkaline electrolyte. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion energy‐storage deviceswith metal Zn as anodes, including batteries and capacitors (ZIBs and ZICs), is largely hindered by dendritic growth and low coulombic efficiency since the side reactions between Zn anodes and electrolyte, originating fromthat targeted and efficient isolation of H2O and SO42− is extremely challenging. Herein, inspired by density functional theory (DFT) that the 2D angstrom level metal‐organic framework(2D‐MOF) is highly selective for the passage of ions, simultaneously excluding the SO42− and H2O but allowing Zn2+ selective conduction. Moreover, 2D‐MOF exhibits better mechanical strength compared with 3D‐MOF, which is more conducive to inhibit dendrite growth. Impressively, benefiting from the 2D‐MOFlayer, symmetric Zn cells survived up to 2000 h at 4 mA cm−2,near 20‐times that of bare Zn anodes. Coupling it with cathode for ZICs and ZIBs, excellent electrochemical performances are presented. Importantly, symmetric Na cells with 2D‐MOF as ionic sieve membrane also deliver small polarization and outstanding performance, indicating that this study provides an efficient strategy to develop long‐life metal anode. [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]

The electric eel is known as the most powerful creature to generate electricity with a discharge voltage up to 860 V and peak current up to 1 A. These surprising properties are the results of billions of years of evolution on the electrical biological structure and bulk, and now have triggered great research interest in electric eel biomimetics for designing innovated configurations and components of energy storage and conversion devices. In this review, first, the bioelectrical behavior of electric eels is surveyed, followed by the physiological structure to reveal the discharge characteristics and principles of electric organs and electrocytes. Additionally, underlying electrochemical mechanisms and models for calculating the potential and current of electrocytes are presented. Central to this review is the recent progress of electric‐eel‐inspired innovations and applications for energy storage and conversion, particularly including novel power sources, triboelectric nanogenerators, and nanochannel ion‐selective membranes for salinity gradient energy harvesting. Finally, insights on the challenges at the moment and the perspectives on the future research prospects are critically compiled. It is suggested that energy‐related electric eel biomimetics will greatly boost the development of next‐generation high performance, green, and functional electronics. [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]

Heterointerface engineering has been verified to be an effective approach to enhance the energy density of alkali-ion batteries by resolving inherent shortcomings of single materials. However, the rational construction of heterogeneous composite with abundant heterogeneous interfaces for sodium-ion batteries (SIBs) is still a significant challenge. Herein, inspired by density functional theory calculations, interface engineering can greatly decrease the energy bandgap and migration barrier of Na ions in Sb and Na3Sb phases, as well as enhance the mechanical properties. A porous heterointerface MOFC–Sb is fabricated by utilizing MOF-C as a support and buffer, exhibiting excellent electrochemical performances for sodium storage. The MOF-C–Sb anode with its rich heterointerface presents an improved electrochemical performance of 540.5 mAh g−1 after 100 cycles at 0.1 A g−1, and 515.9 mAh g−1 at 1.6 A g−1 in term of sodium storage, efficiently resolving the serious volume expansion issues of metal Sb. These results indicate the structural superiority of heterointerface-engineered structure and afford valuable information for the rational design and construction of Sb-based anode materials for high-performance electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Highlights: Oxygen-respirable sponge was constructed by carbon dots-assisted synthesis strategy. The hydrophilicity and aerophilicity of Co@C–O–Cs active sites boost oxygen diffusion and the bifunctional oxygen reduction reaction and oxygen evolution reaction activities. Co@C–O–Cs-based Zn-air battery (ZAB) displays excellent specific capacity and stability, and the all-solid-state Co@C–O–Cs-based ZAB exhibits excellent flexibility. Efficient bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are vital for rechargeable Zn-air batteries (ZABs). Herein, an oxygen-respirable sponge-like Co@C–O–Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy. The aerophilic triphase interface of Co@C–O–Cs cathode efficiently boosts oxygen diffusion and transfer. The theoretical calculations and experimental studies revealed that the Co–C–COC active sites can redistribute the local charge density and lower the reaction energy barrier. The Co@C–O–Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm−2 for OER. Moreover, it can drive the liquid ZABs with high peak power density (106.4 mW cm−2), specific capacity (720.7 mAh g−1), outstanding long-term cycle stability (over 750 cycles at 10 mA cm−2), and exhibits excellent feasibility in flexible all-solid-state ZABs. These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries. [ABSTRACT FROM AUTHOR]

3D porous carbon encapsulated SnO 2 nanoparticles composite (SnO 2 -PC) prepared by an efficient in situ methodology was applied as anode for sodium ion batteries (SIBs). It delivered a high reversible specific capacity of 280.1 mAh g −1 after 250 cycles at a current density of 100 mA g −1 , with ultrahigh capacity retention of 91.63%. Notably, it can Exhibit 100 mAh g −1 after 1000 cycles even at a high current density of 1600 mA g −1 . These greatly enhanced electrochemical properties of SnO 2 -PC composite can be attributed to the superior structure that the electrical conductivity of the composite was improved by the porous carbon matrix, moreover, it can serve as a cushion during the process of Na ion insertion/extraction into the composite. Significantly, this kind of in situ synthesis method is portable for other similar composite. [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]

[Display omitted] Zinc ion batteries (ZIBs) suffer from severe corrosion effects and dendrite growth on the unstable anode/electrolyte interface (AEI) during the plating/stripping process. Therefore, it is of great significance to build a stable AEI enabling a long lifetime for ZIBs. Herein, trace tea polyphenols (TP) were introduced firstly as additive of zinc acetate electrolyte to protect zinc anode from corrosion invasion and boost uniform zinc deposition, thus achieving reversible dendrite-free zinc anode. In situ synchrotron radiation X-ray imaging was conducted to illustrate the positive role of TP molecules in the uniform plating process of zinc. The stable AEI induced by the specific adsorption of TP molecules reduced hydrogen and oxygen evolution side reactions and increased the coulombic efficiency. The TP additive with an ultralow dosage of 0.028 g L−1 delivered favorable cycling stability of 720 h at 0.5 mA cm−2 and 0.5 mAh cm−2. The Zn-Na 3 V 2 (PO 4) 3 full cell assembled with the hybrid Zn(Ac) 2 -TP electrolyte contributed an energy density of 130 mAh g−1 at the current density of 0.2C and enhanced cycling stability of 78% retention after 300 cycles. These results will provide new insights into additive engineering for aqueous electrolytes and the fundamental understanding of AEI phenomena for high performance ZIBs. [ABSTRACT FROM AUTHOR]

With the large-scale application of lithium-ion batteries, the recycling of retired LIBs has been a crucial problem to address. Among the spent LIBs, LiFePO4 (LFP) recycling is urgently needed as it is one of the most extensively utilized cathodes in the sustainable development of LIBs. However, traditional pyro-/hydro-metallurgical recycling methods are normally complicated and uneconomical. Here, we exhibit an efficient and green method with a simple route to regenerate a degraded LiFePO4 cathode, through which the cathode sheets are directly broken down into aluminum foil, high-purity FePO4 and lithium-containing solution by the introduction of hydrogen peroxide as a leaching reagent. The leaching efficiency of Li exceeds 96.3% with scarce Al and Fe, and the regenerated LiFePO4 from recovered FePO4 displays excellent rate capability and long-term cycling stability. This research greatly reduces the processing steps and chemical consumption, which is conducive to the sustainable industrial development of spent lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Interfacial coupling strategy has allured extensive attention for the possibility to endow active electrode materials with superior performance. However, the design of strong coupling engineering with interfacial evolution during electrochemical processes is very challenging. Herein, inspired by the powerful robotic arms and density functional theory calculations, multiple functional groups identified with intense affinity to V atom are successfully grafted on carbon nanotubes (CNTs), thereby in situ building robust interfacial bonds (VOC and VC) to tightly anchor VS4 particles. The largely decreased band gaps and energy barriers show the fortified conductivity of VS4‐CNT heterostructure. Besides, the spacial confinement effect induced by interfacial linkages substantively enhances the mechanical properties to inhibit structural collapse, and restrains the dissolution of polysulfides as verified by molecular dynamics simulations, thus prolonging life span. Excellent energy density of 105.5 Wh kg–1 can be delivered after assembling full sodium‐ion capacitors (activated carbon//VS4‐CNT). Significantly, the reversible interfacial bonds confirmed by various ex situ characteristics during discharge/charge processes hold the key to remarkable sodium storage ability and prominent initial coulombic efficiency. More impressively, strong interfacial coupling effect can establish synergistic soft‐rigid integrated solid‐electrolyte interphase film, which is conducive to elevating the electrochemical performance of electrodes, convincingly constructing advanced sodium‐ion capacitors. [ABSTRACT FROM AUTHOR]

Highlights: The classification of metal–organic frameworks (MOFs) is summarized: MOFs can be divided into one, two and three dimensions based on the skeletal structure, MOFs can be divided into isoreticular metal organic frameworks, zeolitic imidazolate frameworks, and so on according to the ligand. The preparation methods of MOFs are reviewed, which can be divided into traditional one pot method and the emerging preparation methods. The application of MOF materials, MOF composite materials, and MOFs-derived materials in supercapacitor is emphasized. Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems. Metal–organic frameworks (MOFs), as a new type of porous material, show the advantages of large specific surface area, high porosity, low density, and adjustable pore size, exhibiting a broad application prospect in the field of electrocatalytic reactions, batteries, particularly in the field of supercapacitors. This comprehensive review outlines the recent progress in synthetic methods and electrochemical performances of MOF materials, as well as their applications in supercapacitors. Additionally, the superiorities of MOFs-related materials are highlighted, while major challenges or opportunities for future research on them for electrochemical supercapacitors have been discussed and displayed, along with extensive experimental experiences. [ABSTRACT FROM AUTHOR]

Antimony-based materials represent promising anode materials for sodium ion batteries (SIBs) owing to their high theoretical capacity, however, the large volume expansion and low ionic conductivity during the electrochemical process prohibit them from reaching their theoretical expectations. In this work, Sb 2 S 3 @C and Sb 2 Se 3 @C nanodots with uniform diameters of 19.0 nm and 20.7 nm were synthesized by H 2 /C thermal reduction and co-sulfurization (selenization) of sodium stibogluconate. Each Sb 2 S 3 and Sb 2 Se 3 nanodot was coated by an interconnecting carbon network with weak graphitization, which further crosslinked together to form a high conductive framework. When applied as anode for SIBs, they exhibited desired sodium storage properties, especially the excellent cycling stability of Sb 2 Se 3 @C nanodots with a reversible capacity of 316.1 mA h g−1 after 100 cycles at 100 mA g−1 and 269.1 mA h g−1 after 200 cycles at 1 A g−1, which was consistent with the calculated result of theoretical volume changes (264% and 246%) and density functional theory (DFT) calculation for both materials during the Na+ intercalation processes, as expected. [Display omitted] • Sb 2 S 3 (Sb 2 S 3) nanodots/C composites have been successfully fabricated. • The volume changes of two materials during the Na+ insertion/deintercalation process have been calculated and analyzed in details. • The satisfactory sodium storage properties are achieved, which is consistent with the result of theoretical calculation. [ABSTRACT FROM AUTHOR]

The ever‐increasing energy density requirements in electric vehicles (EVs) have boosted the development of Ni‐rich layered oxide cathodes for state‐of‐the‐art lithium‐ion batteries. Nevertheless, the commercialization of polycrystalline Ni‐rich cathodes (PCNCs) is hindered by the severe performance degradation and safety concerns that are tightly related to its particle cracking during cycling. Single‐crystalline Ni‐rich cathodes (SCNCs) with eliminated grain boundaries and high mechanical strength have recently attracted extensive attention owing to their superior structural and cycling stability, which present high crack resistance during electrochemical operation. Various articles have focused on the trial‐and‐error synthesis and modifications of SCNCs, as well as the comparison of performances and mechanisms with PCNCs. However, there has been much less effort in systematic analysis and summary to reveal their key challenges, controversies, and the corresponding primary causes. In this review, the advantages and debates in structural and electrochemical properties of SCNCs over PCNCs are summarized to provide fundamental understanding of SCNCs. Then the current practical issues and challenges are comprehensively discussed from the viewpoints of both academia and industry, as well as the proposed modification strategies and underlying mechanisms for SCNCs. The outlook and perspectives are further given to facilitate the commercial applications of SCNCs in high‐performance EVs. [ABSTRACT FROM AUTHOR]

Here we show that P2/O3 biphasic layered structure is originated from internal heterogeneity of "cationic potential" induced by locally compositional non-uniformity, which largely depends on the temperature-driven reaction thermodynamics and kinetics. The clarified material-formation mechanism enables facile design and preparation of P2/O3 biphasic materials with much-improved sodium-storage performances than single-phase one, promoting the exploration of advanced cathodes for sodium-ion batteries. [Display omitted] Sodium layered oxides generally suffer from deep-desodiation instability in P2 structure and sluggish kinetics in O3 structure. It will be great to design P2/O3 biphasic materials that bring the complementary merits of both structures. However, such exploration is hindered by the ambiguous mechanism of material formation. Herein, supported by theoretical simulations and various spectroscopies, we prove that P2/O3 biphasic structures essentially originate from the internal heterogeneity of cationic potential, which can be realized by constraining the temperature-driven ion diffusion during solid-state reactions. Consequently, P2/O3 biphasic Na 0.7 Ni 0.2 Cu 0.1 Fe 0.2 Mn 0.5 O 2– δ with well-designed quaternary composition is successfully obtained, exhibiting much-improved rate capabilities (62 mAh g−1 at 2.4 A g−1) and cycling stabilities (84% capacity retention after 500 cycles) than its single-phase analogues. Furthermore, synchrotron-based diffraction and X-ray absorption spectroscopy are employed to unravel the underlying sodium-storage mechanism of the P2/O3 biphasic structure. This work presents new insights toward the rational design of advanced layered cathodes for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The accurate and sensitive detection of survivin mRNA is of great significance for cancer diagnosis and treatment. However, limited by the low-abundance mRNA in live cells, most strategies of survivin mRNA detection that were one-to-one signal-triggered model (one target triggered one signal) were inapplicable in practice. Here, we reported a binding-induced DNAzyme motor triggered by the survivin mRNA, which was a one-to-more signal-triggered model (one target triggered more signals), amplifying the detection signal and enhancing the sensitivity. The nanomotor is constructed by assembling several DNAzyme motor strands silenced by the blocker strands, and dozens of FAM-labeled substrate strands on a single gold nanoparticle (AuNP), forming three-dimensional DNA tracks. Through building the survivin mRNA bridge between the blocker and the DNAzyme motor strand, the binding-induced DNA nanomotor could be triggered by survivin mRNA. The operation of the DNAzyme motor was self-powered. And each walking step of the DNAzyme motor was fueled by DNAzyme-catalyzed substrate cleavage, along with the cleavage of the fluorescent molecule, resulting in autonomous and progressive walking along the AuNP-based tracks, and the fluorescence increase. The DNAzyme motor exhibited excellent sensitivity and remarkable specificity for survivin mRNA, providing the potential for cell image. [ABSTRACT FROM AUTHOR]

The practical implementation of Zn metal anodes with high volumetric capacity is seriously plagued by the dendritic growth and accompanying interfacial parasitic reactions. Herein, high yield carbon dots (CDs) with abundant polar functional groups (CHO and CN), as a functional artificial interface layer, are rationally designed to optimize electrolyte/Zn interfaces with large‐scale viability. Of particular note, the quantum‐sized CDs with strong Zn affinity can effectively ameliorate the electric field distribution and ensure that more Zn2+ is adsorbed onto the whole electrode, which are beneficial for lowering the barrier of Zn2+ nucleation and inducing homogeneous Zn deposition, thus rendering a dendrite‐free Zn anode, as extensively confirmed by in situ optical microscope observation and finite element simulation. Meanwhile, the dense and insoluble coating layer with abundant polar functional groups is conducive to arousing the repulsion effect, which is good for shielding the active water and SO42−, thus eliminating the water‐mediated parasitic reactions and improving Zn2+ reaction kinetics. More importantly, the electrochemically stable CDs layer endows the Zn anode with a prolonged lifespan of 3000 h at 1 mA cm−2. This feasible and efficient fabrication of functional CDs layer opens a new avenue for stable dendrite‐free metal anodes. [ABSTRACT FROM AUTHOR]

Highlights: The chemical process of local oxidation–partial reduction–deep coupling for stibnite reduction of carbon dots (CDs) is revealed by in-situ high-temperature X-ray diffraction. Sb2S3@xCDs anode delivers high initial coulombic efficiency in lithium ion batteries (85.2%) and sodium ion batteries (82.9%), respectively. C–S bond influenced by oxygen-rich carbon matrix can restrain the conversion of sulfur to sulfite, well confirmed by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations. CDs-induced Sb–O–C bond is proved to effectively regulate the interfacial electronic structure. The application of Sb2S3 with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency (ICE). In this work, natural stibnite modified by carbon dots (Sb2S3@xCDs) is elaborately designed with high ICE. Greatly, chemical processes of local oxidation–partial reduction–deep coupling for stibnite reduction of CDs are clearly demonstrated, confirmed with in situ high-temperature X-ray diffraction. More impressively, the ICE for lithium-ion batteries (LIBs) is enhanced to 85%, through the effect of oxygen-rich carbon matrix on C–S bonds which inhibit the conversion of sulfur to sulfite, well supported by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations. Not than less, it is found that Sb–O–C bonds existed in the interface effectively promote the electronic conductivity and expedite ion transmission by reducing the bandgap and restraining the slip of the dislocation. As a result, the optimal sample delivers a tremendous reversible capacity of 660 mAh g−1 in LIBs at a high current rate of 5 A g−1. This work provides a new methodology for enhancing the electrochemical energy storage performance of metal sulfides, especially for improving the ICE. [ABSTRACT FROM AUTHOR]

Bi-doped carbon dots (Bi-CDs) with rich polar groups and good compatibility were employed as co-deposition electrolyte additives to homogenize Li+ flux for dendrite-free Li deposition. High coulombic efficiency (99.0%) and long-term stability (800 h) with reduced overpotential (∼15 mV) were achieved after introducing Bi-CDs in conventional electrolyte for high-performance Li–S batteries. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are considered as excellent structural regulator for metal oxides (MOs) due to their abundant functional groups, superior dispersibility, and ultrasmall size (<10 nm). Herein, a new approach is proposed to construct porous pomegranate‐like MOs/CDs composite based on the CDs‐induced in situ growth mechanism of ion adsorption–multipoint surface nucleation–crosslinking agglomeration. The proposed methodology is successfully applied to prepare SnO2/CDs, Cu2O/CDs, and Fe2O3/CDs composites, respectively, demonstrating its universality to metal oxides. Taking SnO2/CDs composite as a case study for anode material in lithium‐ion batteries, it exhibits high lithium storage capacity, excellent cycling stability, and a special feature of capacity increase upon cycling. This study provides a new idea for the design of metal oxides materials tuned by CDs and broadens the application of CDs in the field of material synthesis. [ABSTRACT FROM AUTHOR]