Favorable Rate Capability Research Articles

Nickel-mediated V4O7 as high-performance cathode material for aqueous Zn-ion batteries

Vanadium-based materials are currently favored by researchers due to their multi-structure, which can enhance the steric resistance and electrostatic repulsion during the (de)intercalation process of zinc ions. However, their low conductivity remains an inherent hindrance to their practical application. Therefore, finding a way to adjust the electronic structure of vanadium-based compounds is considered an effective strategy. Presently, we have designed a porous Ni-mediated V4O7, wherein the presence of oxygen defects and heterostructures in V4O7/NiO (Od-NVO-4) substantially improves the diffusion kinetics of ions/electrons and boosts the electrochemical performance. As anticipated, the Zn//V4O7/NiO battery exhibits a high specific capacity (348.6 mAh g−1 at 0.1 A g−1), favorable rate capability (323.8 mAh g−1 at 4 A g−1), and remarkable cycle stability (206.3 mAh g−1 at 2 A g−1 after 2000 cycles). Additionally, the underlying mechanism of electrochemical zinc storage is comprehensively described through electrochemical kinetic analysis and theoretical calculations. These results unambiguously reveal the intrinsic link between the surface/interface structure and electrochemical performance of the cathode, offering a valuable reference for designing high-performance electrode materials.

Conformal Sodium Deposition Facilitated by Ion Adsorption‐Intercalation Process within Hetero‐Interface for Stable Sodium Metal Batteries

AbstractSodium (Na) metal battery is regarded as one of the most promising candidates for large‐scale energy storage devices, benefiting from the abundant sodium reserves and low cost. However, its practical application is hindered by the dendrite growth and unstable electrode‐electrolyte interface. Herein, a 3D sodiophilic structure composed of a carbon matrix overlaid with g‐C3N4 coating layers (g‐C3N4/3D‐C) is designed to stabilize the Na plating/stripping behavior. The sodiophilicity is endowed by a highly reversible adsorption‐intercalation process at the hetero‐interface, which can guide conformal Na deposition and induce the formation of inorganic‐rich solid‐electrolyte interphases with high structural stability and fast Na‐ion transport. Meanwhile, the 3D scaffold can effectively accommodate Na deposition during Na plating/stripping and depress the dendrite formation. As a result, the half cell assembled with g‐C3N4/3D‐C electrode delivers long‐term cycling performance at 1.0 mA cm−2 with a high Coulombic efficiency of 99.92% for over 2000 cycles and of 99.94% even at 5 mA cm−2, 10 mAh cm−2. The practical feasibility of the g‐C3N4/3D‐C is verified with full cells, which shows favorable rate capability and long‐cycle performance. The sodiophilic hetero‐interface construction strategy proposed in this work sparks new insights for designing high‐performance Na metal anodes.

VO2·xH2O nanoribbons as high-capacity cathode material for aqueous zinc-ion batteries: Electrolyte selection and performance optimization

In the pursuit of efficient energy storage solutions for renewable energy, aqueous zinc-ion batteries (ZIBs) have emerged as promising contenders, offering high capacity and manufacturability. Among transition metal oxides, vanadium dioxide (VO2) stands out as the synergestic behavior of H+ and Zn2+ ions with the VO2·xH2O ensures high specific capacity in Zn-ion based battery. Here, we present the successful synthesis of hydrated vanadium oxide (VO2·xH2O) nanoribbons via the hydrothermal method, followed by comprehensive characterizations to assess material properties. A systematic study on electrolyte selection, focusing on achieving high capacity and stability, was conducted using varying electrolyte types and concentrations. The superior 3 M Zn(CF3SO3)2 electrolyte was chosen for further electrochemical investigations, leading to the formation of a two-electrode system comprising VO2·xH2O//Zn half-cell ZIB, which lasts more than 1000 cycles at 1 A g−1 in addition to capacity retention of 82.18% while providing a capacity of 235.63 mAh g−1 at 0.1 A g−1, while demonstrating favorable rate capability. Ex-situ XRD analysis unveiled insights into the designed ZIB's charging/discharging mechanism, showcasing variations in cathode crystallinity and the formation of Zn(OH)2 peaks during cycling. To establish the effective usage of this formed ZIB for daily-life applications, the coin cell was effectively used to power an LED and LCD screen, and the subsequently attained value of capacity was compared along with the available literature. This work surpasses existing ZIBs in terms of capacity and cyclability, paving the way for a more sustainable future through efficient energy storage from renewable sources.

Rapid Release of Silicon by Ultrafast Joule Heating Generates Mechanically Stable Shell-Shell Si/C Anodes with Dominant Inward Deformation.

As a promising anode material, silicon-carbon composites encounter great challenges related to internal stress release and contact between the composites during lithiation. These issues lead to material degradation and concomitantly rapid capacity decline. Here, we report a type of shell-shell silicon-carbon (SS-Si/C) composite, which consists of a carbon shell tightly coated with a silicon shell. The mechanical analysis unveils that the dominant inward expansion of the Si shell is achieved through the synergistic effect of the outer carbon shell and the inner hollow structure. Benefiting from the well-tailored shell-shell structure, the SS-Si/C anode exhibits exceptional performance, boasting a high specific capacity (1690.3 mA h g-1 after 550 cycles at 0.5 A g-1), a high areal capacity (2.05 mA h cm-2 after more than 400 cycles at 0.5 mA cm-2), and an extended cycling life (1055.6 mA h g-1 after 1000 cycles at 8 A g-1), far exceeding commercially available Si/C anodes. Using the well-designed SS-Si/C anode, full cells assembled with LiCoO2 (LCO) or LiFePO4 (LFP) cathodes achieve favorable rate capability and cyclic stability. Notably, at a high rate of 6 C (1 C = 170 and 270 mA g-1 for LFP and LCO, respectively), these full cells deliver high specific capacities of 79.5 mA h g-1 and 64.9 mA h g-1 when using LCO and LFP, respectively, demonstrating the potential of SS-Si/C anodes for practical applications. The straightforward and safe synthesis method in this work enables the rational design of hollow structures with distinct properties.

Li (200) with in-situ generated high entropy alloy/oxide fillers and Li2O enabling desirable Li metal anode

The development of Li metal batteries (LMBs) with high-energy density is impeded by the uncontrollable growth of Li dendrites. In this work, the Li foil is cold-pressed with ball-milled high entropy Mg/Ni/Co/Cu/Zn-based oxides (HEO), which can in-situ generate high entropy alloy/oxide and Li2O in the bulk phase and surface of composited Li anode (denoted as HEA/O@Li). During the cold-pressing process, the Li foil with polycrystalline nature transform into (200) textured Li. The in-situ generated Li2O can provide more lithiophilic sites and enrich the inorganic components of solid state interface (SEI), while the HEA/O fillers dispersed in the composited Li anode can strength corresponding mechanical stability and tune the Li+ stripping/plating process. As a result, the HEA/O@Li exhibits outstanding cycle stability for almost 1000 h at 1 mA cm−2 with fixed area capacity of 1 mAh cm−2. Moreover, the full batteries matched with LiFePO4 cathode demonstrate favorable cycling stability (110 mAh g−1 at 0.5C after 700 cycles) and rate capability.

Ultrafine Iron Boride as a Highly Efficient Nanocatalyst Expedites Sulfur Redox Electrochemistry for High‐Performance Lithium‐Sulfur Batteries

AbstractLithium‐sulfur (Li−S) batteries have garnered significant interest as a strong contender for future energy storage, characterized by their remarkable energy density and cost‐effectiveness. However, the sluggish conversion kinetics of the polysulfide intermediates, compounded with their shuttling behaviors, pose considerable challenges in sulfur electrochemistry. Herein, we develop a novel iron monoboride (FeB) electrocatalyst for boosting sulfur reactions and enhancing Li−S battery performance. The ultrafine powdery FeB affords abundant and fully exposed active interfaces for host‐guest interactions. Meanwhile, the intrinsic high conductivity of FeB, combined with its strong adsorption and catalytic activity to polysulfides, enables substantial inhibition of the shuttle effect and enhancement of conversion kinetics. As a result, sulfur electrodes equipped with the FeB nanocatalyst realize excellent cyclability with a minimal capacity fading of 0.04 % per cycle over 500 cycles, as well as favorable rate capability up to 7 C. Moreover, decent areal capacity and cycling stability can be also achieved under high‐loading (5.1 mg cm−2) and limited‐electrolyte (7.0 mL g−1) configurations. This study presents a facile approach and insightful perspective on nanostructured metal boride for highly efficient sulfur electrocatalysis, holding good promise for the advancement of high‐performance Li−S batteries.

Growing-fruits-type nanoarchitectonics of nickel‑vanadium layered double hydroxide on branches of nitrogen-rich carbon nanotube for high performance supercapacitors

An innovative structural design leverages the distinctive properties inherent in each material of three type electrode material for supercapacitors. First, polyaniline nanotubes (PN) are prepared controllably. Subsequently, the PN are carbonized into nitrogen-rich carbon nanotubes (NCN) to exploit their high electrical conductivity. Finally, a nickel‑vanadium layered double hydroxide (NiV-LDH) is grown on the surface of NCN “branches” to fabricate a nitrogen-rich carbon nanotubes/nickel‑vanadium layered double hydroxide composite material (NCN/NiV-LDH). The NCN/NiV-LDH exhibits an impressive specific capacitance of 1018.2 F g−1 at a current density of 2 A g−1, and demonstrates favorable rate capability as the capacitance value remains at 702.2 F g−1 even when the current density is tripled. Moreover, the assembled asymmetric supercapacitor comprising NCN/NiV-LDH and active carbon (AC) as the positive and negative electrodes, respectively, achieves a high energy density of 108.25 Wh kg−1, even under a power density of 7500 W kg−1.

Restrained Li|Garnet Interface Contact Deterioration Manipulated by Lithium Modification for Solid‐State Batteries

AbstractGarnet 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.

Recyclable fabrication of hollow N-doped amorphous carbon nanospindles with abundant short-range curved carbon fragments as bifunctional anode for lithium/sodium ion storage

A recyclable hard-template method is proposed to exploit spindle-shaped hollow nitrogen-doped amorphous carbon (h-NAC) with a large number of short-range curved carbon fragments as anodes for lithium/sodium ion batteries (LIBs/SIBs). Besides providing adsorption sites due to the high existence of oxygen-containing functional groups (CO and COOH), the heavily exposed edge regions also provide a favorable storage environment with high adsorption energy for Li+/Na+ due to their short-range curved structure. Importantly, the etching solution of hard templates can be recycled to generate the FeOOH nanospindles as a precursor through a simple chemical titration, which supplies a new idea for the green preparation of hollow materials. The h-NAC electrode is proven to be bifunctional for storing lithium and sodium ions, displaying favorable rate capability (255 mAh g−1 and 106 mAh g−1 at 5 A g−1 for LIBs and SIBs, respectively). After 1000 cycles at 1 A g−1, the reproducible capacities of the LIBs and SIBs kept 496 mAh g−1 and 181 mAh g−1, respectively.

A Protocol for Predicting Lithium-Ion Battery Performances Reflecting the Three-Dimensional Structure of Electrodes

As social needs for higher capacity and longer life of lithium-ion batteries increase, shortening the period from research to development and commercialization of batteries has become an extremely important issue. To minimize the above period, a protocol for predicting the performances of (lithium-ion) batteries is highly urged for. Many reports have been published so far regarding the simulation technology of charge-discharge profiles of lithium-ion batteries.1,2 However, in most of simulations, the porous structure of lithium-ion battery electrodes is simplified into a 1D or 2D models. To achieve more accurate battery performance prediction, we adopted the actual 3D structure of the positive and negative electrodes of lithium-ion batteries in simulations.A plasma FIB SEM (Helious5, Thermofisher Scientific Inc.) was used to obtain the 3D structures of the positive and negative electrodes of the lithium-ion battery. The porosity and tortuosity of the electrodes were calculated by reconstructing a 3D image and performing image analysis. Based on this 3D structure, we also calculated the lithium ion conductivity in the electrode. The obtained 3D structural parameters were applied to the simulation of battery characteristics and compared with actual charge/discharge test results. We have also developed a performance prediction protocol that allows to reflect the measured physical properties of battery materials in the simulation.Figure 1 shows cross-sectional images of two different high-nickel-type positive electrodes prepared under different experimental conditions. It can be seen that the active materials are packed densely for both the electrodes, but the level of conductive carbon and binder dispersion is different. The particle size distribution of the active materials was also found to be largely different between the two samples. Structural parameters were obtained from the 3D structure by image analysis, and highly accurate performance prediction was performed. It can be predicted that the rate capability reflects the structural homogeneity. Also, the simulation revealed that the particle size distribution plays an important role for achieving favorable rate capability. Acknowledgement This work was financially supported by the NEXT Center of Innovation Program (COI-NEXT, Grant Number JPMJPF2016) of the Japan Science and Technology Agency. References (1) M Doyle , J. Newman, A. S. Gozdz, C . N. Schmts, and M. Tarascon, J. Electrochem. Soc. 1996, 143, 1890(2) G. Li and C. W. Monroe, Annu. Rev. Chem. Biomol. Eng. 2020, 11 277. Figure 1

Human friendly biodegradable supercapacitors utilizing water-soluble MoOx@Mo-foil as electrode and normal saline as electrolyte

The rapid advancement of biomedical technology has sparked increasing interest in developing biodegradable implantable energy storage devices for applications in biosensors and bioelectronics. However, the limited energy density, biocompatibility, and degradability of existing materials have posed significant challenges to their widespread adoption in the biomedical field. In response, this study presents an electrode material for a solid-state biodegradable supercapacitor consisting of an array structure of molybdenum oxide (MoOx) nanosheets in situ grown on water-soluble molybdenum foil (Mo-foil). The MoOx@Mo-foil electrode exhibits exceptional electrochemical performance, suppressing previous designs. It demonstrated a high capacitance of 433.3 F/g at 1 A/g, and even at 10 A/g, it has a favorable rate capability of 48.9%. Furthermore, cycling stability test revealed an outstanding endurance, with an impressive retention of 88.0% after 5000 cycles. An symmetrical supercapacitor was assembled by combining two MoOx@Mo-foil electrodes with remarkable energy storage capabilities and cycling stability of 94.3% over 5000 cycles. Additionally, the biodegradable supercapacitor exhibited a high energy density of 40.95 Wh/kg at 600.48 W/kg. Moreover, the device is fully biodegradable, which paves the way for advancing the field of bioelectronics and propelling the development of sustainable energy storage technologies for biomedical applications.

Dually Sulphophilic Chromium Boride Nanocatalyst Boosting Sulfur Conversion Kinetics Toward High-Performance Lithium-Sulfur Batteries.

The sluggish kinetics of sulfur conversions have long been hindering the implementation of fast and efficient sulfur electrochemistry in lithium-sulfur (Li-S) batteries. In this regard, herein the unique chromium boride (CrB) is developed via a well-confined mild-temperature thermal reaction to serve as an advanced sulfur electrocatalyst. Its interstitial-alloy nature features excellent conductivity, while the nano-lamination architecture affords abundant active sites for host-guest interactions. More importantly, the CrB nanocatalyst demonstrates a dual sulphophilicity with simultaneous Cr─S and B─S bondage for establishing strong interactions with the intermediate polysulfides. As a result, significant stabilization and promotion of sulfur redox behavior can be achieved, enabling an excellent Li-S cell cyclability with a minimum capacity fading rate of 0.0176% per cycle over 2000 cycles and a favorable rate capability up to 7C. Additionally, a high areal capacity of 5.2mAhcm-2 , and decent cycling and rate performances are still attainable under high sulfur loading and low electrolyte dosage. This work offers a facile approach and instructive insights into metal boride sulfur electrocatalyst, holding a good promise for pursuing high-efficiency sulfur electrochemistry and high-performance Li-S batteries.

Rational design of one-dimensional skin-core multilayer structure for electrospun carbon nanofibers with bicontinuous electron/ion transport toward high-performance supercapacitors

The fast transport of electrons and ions within electrodes is crucial to the final electrochemical properties. Herein, we have developed a unique ultra-long one-dimensional (1D) skin-core multilayer structure based on electrospun carbon nanofibers mainly through a facile Stöber method combined with resorcinol–formaldehyde resin, which not only achieves bicontinuous electron/ion transport during the charge/discharge process, but also provides large surface area for ion adsorption. Particularly, controlling the number of active layers as well as regulating the active sites in layer both can obviously improve capacitive properties. Benefiting from the synergistic effects of the desirable architecture, such the rational-designed skin-core structural carbon nanofibers as supercapacitor electrode can deliver a high specific capacitance up to 255 F g−1 at 0.5 A g−1, favorable rate capability with 89% capacitance retention of initial capacitance at 8 A g−1, and excellent cycling stability with nearly 93% capacity retention after 10,000 cycles at 2 A g−1. Furthermore, the as-assembled symmetric supercapacitor devices also present a maximum energy density of 8.77 Wh kg−1 at 0.25 kW kg−1 and a maximum power density of 3.70 kW kg−1 at 6.74 Wh kg−1. Such skin-core carbon nanofibers provide an effective strategy to design high-performance supercapacitor electrode for the next-generation energy storage devices.

Stabilize Sodium Metal Anode by Integrated Patterning of Laser-Induced Graphene with Regulated Na Deposition Behavior.

Metallic sodium is regarded as the most potential anode for sodium-ion batteries due to its high capacity and earth-abundancy. Nevertheless, uncontrolled Na dendrite growth and infinite volume change remain great challenges for developing high-performance sodium metal batteries. This work provides a simple and general approach to stabilize sodium metal anode (SMA) by constructing Sn nanoparticles-anchored laser-induced graphene on copper foil (Sn@LIG@Cu) consisting of Sn@LIG composite, polyimide (PI) columns, and Cu current collector. The Sn-based sodiophilic species effectively reduce the Na nucleation overpotential and regulate the dendrite Na-free deposition. While the flexible PI columns act as binder and buffer the volume variation of Na during cycling. Besides, the unique patterned structure provides continuous and rapid channels for ion transportation, promoting the Na+ transport kinetics. Therefore, the as-fabricated Sn@LIG@Cu electrode exhibits outstanding rate performance to 40mA cm-2 and excellent cycling stability without dendrite growth, which is confirmed by in-situ optical microscopy observation. Moreover, the practical full cell based on such an anode displays a favorable rate capability of up to 10 C and cycling performance at 5 C for 600 cycles. This work thus demonstrates a facile, highly-efficient, and scalable approach to stabilize SMAs and can be extended to other battery systems.

Nitrogen-doped hollow carbon nanoparticles with optimized multiscale nanostructures via dolomite-assisted chemical vapor deposition for high-performance potassium-ion capacitor

Carbon-based materials are considered as promising anode candidates for potassium-ion storage with the key bottlenecks lying in the slow kinetics and huge volume expansion caused by the large size of K+. Herein, nitrogen-doped hollow carbon nanoparticles (NHCP) with optimized multiscale nanostructures are synthesized by a natural template-assisted chemical vapor deposition process. Benefiting from the stacking nanoparticles structure with hierarchical pores, high level of pyridinic-/pyrrolic-N, and enlarged interlayer spacing, the constructed NHCP anode delivers superior K+ storage properties in terms of high reversible capacity (412.7 mAh g−1 at 0.03 A g−1), favorable rate capability, and long cyclic stability. The detailed experimental and computational studies reveal the combined storage mechanism of K+ adsorption and insertion in the multiscale nanostructure of NHCP. To achieve high areal capacities, self-supported NHCP electrodes with high mass loadings (3.41 and 6.23 mg cm−2) were constructed by a vacuum-assisted infiltration process which exhibits greatly improved areal capacities as compared with the traditional slurry coating electrode. The assembled full-carbon potassium-ion capacitor based on NHCP anode exhibits high energy and power densities (168 Wh kg−1 and 9.4 kW kg−1) and a long cycling lifespan (83.9% capacity retention after 10000 cycles at 1.0 A g−1). This work provides a facile fabrication method for porous carbon electrodes with high mass loadings and capacities, which holds the potential for practical application.

Hard-soft carbon with tailored graphitization for high performance supercapacitors

There is always a mutual inhibition relationship between porosity and electrical conductivity. Rational design of hard-soft carbon to regulate the graphitization degree is an effective strategy to solve this problem. Herein, we reported an efficient method to synthesize hard-soft carbon by grafting polyaniline (PANI) onto carboxymethyl chitosan (CMC), followed by calcination with potassium oxalate. The CMC-PANI derived carbon (CPC) exhibits an interconnected framework with a high specific surface area. The graphitization degree can be controlled by the grafting ratio of PANI. The highly uniform distribution of hard-soft carbon increases the electrical conductivity which permits fast electrons/ions transfer. Benefiting from these features, CPC-3 delivers an enhanced specific capacitance of 337 F g−1 at 1 A g−1. The CV curves of the assembled symmetric supercapacitors (SCs) have no obvious distortion even at the scan rate of 500 mV s−1, indicating a favorable rate capability. The SCs manifest the maximum energy density of 28.72 Wh Kg−1 at a power density of 450 W kg−1, as well as excellent cycle stability with 97.5 % capacity retention after 5000 cycles at 10 A g−1. This work affords a new sight to prepare uniformly distributed hard-soft carbon materials for SCs with high cycle stability and rate performance.

Sodium Ion Pre-Intercalation of δ-MnO2 Nanosheets for High Energy Density Aqueous Zinc-Ion Batteries.

With the merits of low cost, environmental friendliness and rich resources, manganese dioxide is considered to be a promising cathode material for aqueous zinc-ion batteries (AZIBs). However, its low ion diffusion and structural instability greatly limit its practical application. Hence, we developed an ion pre-intercalation strategy based on a simple water bath method to grow in situ δ-MnO2 nanosheets on flexible carbon cloth substrate (MnO2), while pre-intercalated Na+ in the interlayer of δ-MnO2 nanosheets (Na-MnO2), which effectively enlarges the layer spacing and enhances the conductivity of Na-MnO2. The prepared Na-MnO2//Zn battery obtained a fairly high capacity of 251 mAh g-1 at a current density of 2 A g-1, a satisfactory cycle life (62.5% of its initial capacity after 500 cycles) and favorable rate capability (96 mAh g-1 at 8 A g-1). Furthermore, this study revealed that the pre-intercalation engineering of alkaline cations is an effective method to boost the properties of δ-MnO2 zinc storage and provides new insights into the construction of high energy density flexible electrodes.

High sulfur loading and shuttle inhibition of advanced sulfur cathode enabled by graphene network skin and N, P, F-doped mesoporous carbon interfaces for ultra-stable lithium sulfur battery

Achieving high loading of active sulfur yet rational regulating the shuttle effect of lithium polysulfide (LiPS) is of great significance in pursuit of high-performance lithium-sulfur (Li-S) battery. Herein, we develop a free-standing graphene-nitrogen (N), phosphorus (P) and fluorine (F) co-doped mesoporous carbon-sulfur (G-NPFMC-S) film, which was used as a binder-free cathode in Li-S battery. The developed mesoporous carbon (MC) achieved a high specific surface area of 921 m²·g^–1 with a uniform pore size distribution of 15 nm. The inserted graphene network inside G-NPFMC-S cathode can effectively improve its electrical conductivity and simultaneously restrict the shuttle of LiPS. A high sulfur loading of 86% was achieved due to the excellent porous structures of graphene-NPFMC (G-NPFMC) composite. When implemented as a freestanding cathode in Li-S battery, this G-NPFMC-S achieved a high specific capacity (1,356 mAh·g^–1), favorable rate capability, and long-term cycling stability up to 500 cycles with a minimum capacity fading rate of 0.025% per cycle, outperforming the corresponding performances of NPFMC-sulfur (NPFMC-S) and MC-sulfur (MC-S). These promising results can be ascribed to the featured structures that formed inside G-NPFMC-S film, as that highly porous NPFMC can provide sufficient storage space for the loading of sulfur, while, the N, P, F-doped carbonic interface and the inserted graphene network help hinder the shuttle of LiPS via chemical adsorption and physical barrier effect. This proposed unique structure can provide a bright prospect in that high mass loading of active sulfur and restriction the shuttle of LiPS can be simultaneously achieved for Li-S battery.

Synergistic Tuning of Nickel Cobalt Selenide@Nickel Telluride Core–Shell Heteroarchitectures for Boosting Overall Urea Electrooxidation and Electrochemical Supercapattery

Herein, we demonstrate the synthesis of bifunctional nickel cobalt selenide@nickel telluride (NixCo12‐xSe@NiTe) core–shell heterostructures via an electrodeposition approach for overall urea electrolysis and supercapacitors. The 3D vertically orientated NiTe dendritic frameworks induce the homogeneous nucleation of 2D NixCo12‐xSe nanosheet arrays along similar crystal directions and bring a strong interfacial binding between the integrated active components. In particular, the optimized Ni6Co6Se@NiTe with an interface coupling effect works in concert to tune the intrinsic activity. It only needs a low overpotential of 1.33 V to yield a current density of 10 mA cm−2 for alkaline urea electrolysis. Meanwhile, the full urea catalysis driven only by Ni6Co6Se@NiTe achieves 10 mA cm−2 at a potential of 1.38 V and can approach a constant level of the current response for 40 h. Besides, the integrated Ni6Co6Se@NiTe electrode delivers an enhanced specific capacity (223 mA h g−1 at 1 A g−1) with a high cycling stability. Consequently, a hybrid asymmetric supercapacitor (HASC) device based on Ni6Co6Se@NiTe exhibits a favorable rate capability and reaches a high energy density of 67.7 Wh kg−1 and a power density of 724.8 W kg−1 with an exceptional capacity retention of 92.4% after sequential 12 000 cycles at 5 A g−1.

Designing Bidirectionally Functional Polymer Electrolytes for Stable Solid Lithium Metal Batteries

AbstractThe development of high energy density lithium metal batteries has been retarded by the uncontrolled lithium dendrite formation and unstable Ni‐rich cathode–electrolyte interface (CEI). Herein, the bidirectionally functional polymer electrolytes (BDFPE) are designed via direct UV solidification of functional polymer species on electrode surfaces to simultaneously handle the interface issues faced by anodes and cathodes. By constructing the BDFPE, a smooth and dendrite‐free lithium deposition is enabled for Li||Li symmetry cells after 1800 h ultralong cycling at 1 mA cm−2 and 1 mAh cm−2, which are attributed to the fast ion conductivity (5.84 × 10−4 S cm−1), high Li+ transfer number (0.69) of BDFPE and low interfacial resistance between electrode and solid electrolytes. Furthermore, Li||LiNi0.6Co0.2Mn0.2O2 batteries demonstrate a favorable cycling and rate capability, and a stable and phosphate‐based CEI layer is constructed in situ. DFT studies reveal that the functional additives FEC and TEP participate in the interface formation. The finding provides a promising design strategy to accommodate the anode and cathode interfaces for high energy density lithium metal batteries.