Robust Cycling Stability Research Articles

Iodine/Chlorine Multi-Electron Conversion Realizes High Energy Density Zinc-Iodine Batteries.

Aqueous zinc-iodine (Zn-I2) batteries are promising energy storage devices; however, the conventional single-electron reaction potential and energy density of iodine cathode are inadequate for practical applications. Activation of high-valence iodine cathode reactions has evoked a compelling direction to developing high-voltage zinc-iodine batteries. Herein, ethylene glycol (EG) is proposed as a co-solvent in a water-in-deep eutectic solvent (WiDES) electrolyte, enabling significant utilization of two-electron-transfer I+/I0/I- reactions and facilitating an additional reversibility of Cl0/Cl- redox reaction. Spectroscopic characterizations and calculations analyses reveal that EG integrates into the Zn2+ solvation structure as a hydrogen-bond donor, competitively binding O atoms in H2O, which triggers a transition from water-rich to water-poor clusters of Zn2+, effectively disrupting the H2O hydrogen-bond network. Consequently, the aqueous Zn-I2 cell achieves an exceptional capacity of 987 mAh gI2 -1 with an energy density of 1278Wh kgI2 -1, marking an enhancement of ≈300 mAh g-1 compared to electrolyte devoid of EG, and enhancing the Coulombic efficiency (CE) from 68.2% to 98.7%. Moreover, the pouch cell exhibits 3.72 mAh cm-2 capacity with an energy density of 4.52 mWh cm-2, exhibiting robust cycling stability. Overall, this work contributes to the further development of high-valence and high-capacity aqueous Zn-I2 batteries.

Heterojunction-structured Ni0.85Se/CoSe nanoparticles anchored on holey graphene for performance-enhanced sodium-ion batteries

Graphene-based metal selenides, are increasingly recognized for their potential in sodium-ion battery applications due to their superior electrochemical properties. The unique structure of graphene facilitates rapid in-plane transport of sodium ions, but the interlayer diffusion remains a significant challenge. The Ni0.85Se@CoSe heterojunctions, strategically grown adjacent to the graphene pores, offer a novel solution by creating in-plane holes that serve as direct channels for vertical ion transport, thereby enhancing cross-layer sodium ion permeation. The incorporation of Ni0.85Se@CoSe heterojunctions with holey graphene (NCS/HG) significantly enhances the reaction dynamics between sodium ions and anode material. These heterojunctions not only promote easier sodium ion insertion/extraction process by reducing the Na+ adsorption energy, but also improve the electrical conductivity by adjusting the band gap. The configuration supports high current density applications (573.5 mAh/g at 5.0 A/g), and ensures robust cycle stability with a capacity retention rate of 97 % after 1000 cycles at 2.0 A/g. Therefore, the development and etching techniques employed in engineering the Ni0.85Se@CoSe/HG graphene-based anodes exemplify a significant advancement in anode material design, highlighting the importance of material architecture in the development of high-performance energy storage devices.

Anthracite-Derived Porous Carbon@MoS2 Heterostructure for Elevated Lithium Storage Regulated by the Middle TiO2 Layer.

The rational design of MoS2/carbon composites have been widely used to improve the lithium storage capability. However, their deep applications remain a big challenge due to the slow electrochemical reaction kinetics of MoS2 and weak bonding between MoS2 and carbon substrates. In this work, anthracite-derived porous carbon (APC) is sequential coated by TiO2 nanoparticles and MoS2 nanosheets via a chemical activation and two-step hydrothermal method, forming the unique APC@TiO2@MoS2 ternary composite. The dynamic analysis, in-situ electrochemical impedance spectroscopy as well as theoretical calculation together demonstrate that this innovative design effectively improves the ion/electron transport behavior and alleviates the large volume expansion during cycles. Furthermore, the introduction of middle TiO2 layer in the composite significantly strengthens the mechanical stability of the entire electrode. As expected, the as-prepared APC@TiO2@MoS2 anode displays a high lithium storage capacity with a reversible capacity of 655.8 mAh g-1 after 150 cycles at 200 mA g-1, and robust cycle stability. Impressively, even at a high current density of 2 A g-1, the electrode maintains a superior reversible capacity of 597.7 mAh g-1 after 1100 cycles. This design highlights a feasibility for the development of low-cost anthracite-derived porous carbon-based electrodes.

One-Step laser induced molybdenum carbide/graphene hybrid electrode for supercapacitor

Transition metal carbides (TMCs) have garnered significant attention in various energy applications owing to their outstanding conductive and electrochemical properties. Despite these advantages, challenges persist in terms of non-toxicity and efficient fabrication methods. In this study, a Mo3C2/laser-induced graphene (LIG) heterostructure was synthesized via one-step CO2 laser induced conversion process. The specific area capacitance of the Mo3C2/LIG hybrid electrode reached 23.5 mF cm−2, which is 2.5 times higher than that of pure Mo3C2 and 9 times greater than pure LIG electrodes. Moreover, the hybrid electrode exhibited robust cycling stability, maintaining 98.4 % of its initial capacitance after 10,000 charge–discharge cycles. Theoretical simulation also revealed superior hydrogen adsorption and high electrical conductivity of the Mo3C2/LIG hybrid electrode. This work presents a promising approach for developing advanced molybdenum carbide-based composites and offers an alternative strategy for enhancing the electrochemical performance of capacitive electrodes.

Carbon-encapsulated silicon ordered nanofiber membranes as high-performance anode material for lithium-ion batteries

Silicon have attracted much attention as a promising anode material for lithium-ion batteries due to the extremely high theoretical capacity. However, its practical application is limited by the huge volume expansion during the cycling process. To address this issue, carbon-encapsulated silicon ordered nanofiber membranes were designed through a modified electrospinning technology with a strong magnetic field. Compared with the conventional nanofiber membranes, the optimized M1200 Gs anode exhibited a high discharge capacity of 1603.1 mAh·g−1 at 0.1 A·g−1, a superior rate performance, and a robust cycling stability with a reversible capacity of 658.1 mAh·g−1 at 1 A·g−1 after 100 cycles. The improved electrochemical performance was confirmed to be highly correlated with the parallel structure of nanofibers, which help to facilitate the diffusion and transport of electrons and ions, realize the stress distribution and buffer the volume changes. This work provides unique insights into designing silicon-based anodes with novel structures for lithium-ion batteries.

A three-in-one strategy of high-entropy, single-crystal, and biphasic approaches to design O3-type layered cathodes for sodium-ion batteries

O3-type layered oxides are promising cathodes for sodium-ion batteries (SIBs). However, severe volume changes, irreversible phase transitions, and sluggish Na+ ion transport kinetics lead to structural collapse and severe capacity loss. Herein, a three-in-one strategy “high entropy, single crystal, and biphase” is proposed to design O3-type layered cathodes for SIBs, which achieves enhanced structural stability and Na+ transport kinetics by the combination effect of multimetal high-entropy, the single crystal, and Li substitution. The as-prepared high-entropy oxide (HEO) cathode, Na(Fe1/6Co1/6Ni1/6Mn1/6Ti1/6)Li1/6O2, exhibits a high reversible capacity of 140.3 mAh g−1, robust cycling stability, exceptional rate capability (86 mAh g−1 at rates of 15C), excellent air-stability, and water-resistance ability. In situ X-ray diffraction reveals that the HEO cathode has highly reversible phase transitions and small volume change (ΔV=3.28 %). Ex situ X-ray absorption spectroscopy reveals that reversible Ni2+/Ni4+, Fe3+/Fe3.6+, and Co3+/Co3.6+ redox couples provide charge compensation for the high-entropy cathode at 2.0∼4.2 V. Notably, the full-cell battery based on the high-entropy cathode and hard carbon anode delivers a specific capacity of 134.3 mAh g−1 and an energy density of 390.8 Wh kg−1. This work provides valuable insights into the design of novel high-performance high-entropy cathodes for SIBs, highlighting a promising avenue for advancing rechargeable battery technology.

Insight into the polysulfides conversion kinetics and its activation energy relationship on ultrafine V8C7 in Li-S batteries

Catalytic conversion of lithium polysulfides (LiPSs) is regarded as an effective approach to boosting kinetics and suppressing shuttling effect in lithium-sulfur (Li-S) batteries, but developing efficient catalysts and understanding of its catalytic mechanism still remain challenges. Herein, the ultrafine V8C7 nanocrystals embedded into the porous N-doped carbon frameworks (V8C7/NC) was designed for accelerating the LiPSs catalytic-conversion kinetics toward high-performance Li-S batteries. We propose that the ultrafine V8C7 nanocrystals with abundant unsaturated coordination atoms increase the active sites for catalytic-conversion of LiPSs and also accelerate the corresponding kinetics by reducing its reaction activation energy, meanwhile the interlinked nano-channels of V8C7/NC can effectively confine LiPSs and also promote electron/ion transfer. These attributes enable the Li-S cell equipped with V8C7/NC to deliver a large discharge capacity of 1393.3 mAh g−1 at 0.2 C, excellent rate capability (496.0 mAh g−1 at 10 C), and robust cycling stability (1000 cycles with a negligible capacity decay rate of 0.019 % per cycle even at 5 C). The innovative concept of ultrafine V8C7 nanocrystals embedded into the porous carbon toward improved LiPSs catalytic-conversion kinetics could be extended to develop other electrocatalytic hosts for high-performance Li-S batteries.

Naphthalene Diimide-Based Cyanovinylene-Containing Conjugated Organic Polymers for Efficient Lithium-Ion Battery Electrodes.

The pursuit of innovative organic materials and the examination of the "structure-function" correlation in lithium-ion batteries (LIBs) are crucial and highly desirable. Current research focuses on the creation of novel conjugated organic polymers with polycarbonyl groups and examining the impact of electrode structure on the function of lithium-ion batteries. In this paper, two novel cyanovinylene-based conjugated organic polymers, NBA-TFB and NBA-TFPB, are synthesized using a Knoevenagel condensation reaction with naphthalene diimide as the integral unit. The performance of NBA-TFB and NBA-TFPB as cathodes in lithium-ion batteries is investigated. Improved conductivity and increased active site density in NBA-TFPB resulted in superior electrochemistry compared to NBA-TFB. Specifically, NBA-TFPB exhibited a larger reversible capacity (87.58 mAh g-1 at 0.2C and 88.34% retention after 100 cycles), exceptional rate capability (66.13 mAh g-1 at 5C), and robust cycling stability (99.58% coulombic efficiency at 1C and 60.71% retention after 2000 cycles). This study expands the family of diimide-based naphthalene polymers and provides a strategy for enhancing the performance of organic electrode materials containing polycarbonyl structure.

Large-Scale Synthesis of N,S Codoped Carbon-Modified Fe0.975S Composites as a Novel Anode for Lithium/Sodium Ion Batteries with Enhanced Performance.

To overcome obstacles hindering the commercialization of lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), we introduce a cost-effective single-step sulfurization strategy for synthesizing iron sulfide (Fe0.975S) nanohybrids, augmented by N,S codoped carbon. The resulting N,S codoped carbon-coated Fe0.975S (Fe0.975S@NSC) electrode exhibits exceptional potential as a highly reversible anode material for both LIBs and SIBs. With impressive initial discharge and charge capacities (1658.2 and 1254.9 mAh g-1 for LIBs and 1450.9 and 1077.1 mAh g-1 for SIBs), the electrode maintains substantial capacity retention (900 mA h g-1 after 1000 cycles for LIBs and 492.5 mA h g-1 after 600 cycles for SIBs at 1.0 A g-1). The LiMn2O4//Fe0.975S@NSC and Na3V2(PO4)3//Fe0.975S@NSC full batteries can maintain excellent reversible capacity and robust cycling stability. Ex situ and in situ X-ray diffraction, density functional theory (DFT) calculations, and kinetics analysis confirm the promising energy storage potential of the Fe0.975S@NSC composite.

Spider silk inspired ultrafine carbon nanotubes-crosslinked porous carbon fibers for Zn-air batteries

There is a critical need for the development of low-cost, highly efficient, and stable bifunctional oxygen electrocatalysts for the advancement of Zn-air battery (ZAB). This study presents an Fe-, Ni-, and N-co-doped porous carbon material (FeNiN-CF-15) synthesized through the pyrolysis of a mixture combining the melamine and electrospun fibers. This material comprises carbon fiber substrates and spider silk-like ultrafine carbon nanotubes (CNTs) catalytically grown from FeNi alloys. With a high N doping level (12.9 at%), large specific surface area (385.18 m2 g−1), and conductive carbon network composed of CNTs, the new electrocatalyst exhibits outstanding bifunctional oxygen electrocatalytic performances. Specifically, it achieves a half-wave potential of 0.853 V for oxygen reduction reaction (ORR) and 1.571 V for oxygen evolution reaction (OER) at 10 mA cm−2. The exceptional ORR/OER electrocatalytic activity enables the FeNiN-CF-15-based liquid ZAB to deliver a high initial energy efficiency of 62.12 %, narrow charging/discharging voltage gap of 0.742 V, and robust cycling stability within 960 cycles for 320 h at 5 mA cm−2. Additionally, the reported electrocatalyst is proven competent for use in a flexible ZAB.

Luffa vines-derived N, O doped porous carbon with high surface area for supercapacitors

Considerable attention has been devoted to creating porous carbons with exceptional surface area and porosity from biomass waste for energy storage devices. Herein, we employed a straightforward high-temperature carbonization and KOH activation method to synthesize nitrogen (N) and oxygen (O) co-doped porous activated carbons derived from luffa vines (LVACs). The impact of varying KOH concentrations on the morphology, structure, and electrochemical properties of LVACs was thoroughly investigated. The optimal mass ratio of KOH to LVACs at 1:6 achieved the maximum specific surface area of 3369 m2 g−1. At a current density of 1 A g−1, the LASC-6 electrode exhibits an impressive specific capacitance of 348.5 F g−1. It also demonstrates exceptional rate performance, retaining 70.6 % of its capacitance at a current density of 20 A g−1. The electrode possesses robust cycling stability, retaining 90 % of the initial capacitance after 5000 cycles. We assessed the practicality of LVAC-6 by constructing symmetric supercapacitors (SSCs) using KOH and [BMIM]BF4 electrolytes. The KOH and [BMIM]BF4 SSCs achieved specific capacitances of 86.75 and 50.31 F g−1, respectively, at a current density of 0.25 A g−1. Moreover, the [BMIM]BF4 SSC exhibited an impressive energy density of 51.05 Wh kg−1 at a power density of 346.15 W kg−1. Therefore, we propose a simple and cost-effective strategy to produce porous carbon materials with excellent electrochemical performance from discarded biomass waste, facilitating the preparation of environmentally friendly electrode materials for high-performance supercapacitors.

Curvature-induced strain to realize differential lithiophilicity for selective lithium deposition and stable lithium anode

Regulating the lithiophilicity of three-dimensional (3D) lithium hosts is crucial for improving lithium deposition and suppressing dendrite growth. However, previous research has mainly focused on varying lithiophilic components, and the impact of geometric structures induced strain remains poorly understood. Herein, we present a novel curvature-induced strain engineering approach to regulate lithiophilicity and deposition kinetics of lithium in lightweight 3D tubular carbon hosts. A hollow carbon fiber with bilateral growth of MnO2 nanosheet arrays both inside and outside the tubes (MnO2@HCFC) have been successfully synthesized. Theoretical calculations and experiments confirm that the MnO2 layers inside and outside the hollow carbon fiber tube undergo compressive and tensile strain, respectively. The curvatures induced strain modifies the O2p band center of the lithiophilic MnO2 layer, enabling the regulation of lithiophilicity and preferential and uniform lithium deposition within the carbon fiber tubes. The MnO2@HCFC framework exhibits excellent lithium affinity and uniform Li+ flux distribution, as evidenced by visualization techniques and COMSOL simulations, enabling dendrite-free lithium deposition. The Li-MnO2@HCFC||LiCoO2 full cell retains 85.7 % of its capacity after 400 cycles at 0.5 C with a high LiCoO2 loading of 10.3 mg cm-2. The optimized lithium anode pouch cell exhibits robust cycle stability under harsh conditions. This work offers new insight into the design of 3D lithium hosts to enhance the performance of lithium anodes through curvature-induced strain engineering.

Copper substituted manganese Prussian blue analogue composite nanostructures for efficient aqueous zinc-ion batteries

Aqueous zinc (Zn)-ion batteries (AZIBs) are considered a promising green energy storage alternative due to their large capacity, low cost, and exceptional safety. Prussian blue analogues (PBAs) with a robust three-dimensional structure and extensive ion channels are highly favorable for Zn2+ insertion/extraction, surpassing manganese (Mn) and vanadium oxides. Herein, copper (Cu) substituted Mn PBA (CuMn PBA) composite nanostructures are synthesized via a simple water-based co-precipitation technique using different concentrations of Cu and Mn sources. The partial substitution of Cu and the formation of Mn vacancies prevent Jahn-Teller distortions of MnN6 octahedra, extending the lifespan. The CuMn PBA-2 electrode exhibits a high discharge capacity of 175.14 mA h g−1 at 0.5 A g−1, superior rate capability of 89.08 mA h g−1 at 2.4 A g−1, and robust cycling stability, maintaining 73.15 mA h g−1 over 2000 cycles at 3 A g−1. Furthermore, the distinct structure provides numerous active sites and reduces volume volatility during cycling. The presence of Cu enhances electrode conductivity, thereby promoting a higher rate of Zn-ion diffusion between electrodes. The reversible intercalation and deintercalation of Zn2+ ions in the CuMn PBA-2 cathode are substantiated by ex-situ analysis methods. This work presents a novel approach for producing high-performance and stable PBA cathode materials for AZIBs.

Machine Learning Accelerated Identification of Bifunctional Active Sites in Metal-Organic Framework Derived Metal Oxide Heterostructures for High-Performance Zinc-Air Batteries

The demand for electrochemical energy storage (ESS) systems and their market size has drastically increased in many applications ranging from portable devices through electric vehicles to large-scale grid systems over the past decades. Yet, a more advanced ESS is required due to the safety issues and limited energy density of currently commercialized lithium-ion batteries (LIBs) for wide and matured applications. As a solution to this challenge, zinc-air batteries (ZABs) have gained tremendous attention due to their high energy density, low cost, environmental friendliness, and much lower fire risk characteristics. ZABs utilize oxygen from the atmosphere at their cathode during discharge, where the atmospheric oxygen is reduced to hydroxide via an oxygen reduction reaction (ORR). On the other hand, hydroxide is released as oxygen via oxygen evolution reaction (OER) during charge. The fact that oxygen is drawn directly from the air enables high gravimetric and volumetric energy densities of ZABs compared to those of commercial LIBs. However, the sluggish kinetics of the four-electron transfer steps in ORR and the mass transport of oxygen in OER remain major challenges for the practical application of ZABs. Meanwhile, precious metal-based catalysts such as Pt/C and RuO2 are known to have good catalytic activity towards ORR and OER. However, the integration of different catalysts into the same cathode is very difficult. Additionally, the high cost and natural scarcity of novel metals limit their usage for practical applications.We synthesized a bifunctional CoO/Mn3O4 heterostructure (CMH) OER/ORR electrocatalyst which was derived from metal-organic framework (MOF) for excellent activities in ZABs. The CMH cathode exhibited high ORR and OER performances, as demonstrated by the higher ORR current density than that of the Pt/C catalyst as well as the low OER overpotential exceeding those of the RuO2 catalyst. Remarkably, atomic structures of the CMH were elucidated using global optimization of genetic algorithm integrated with the machine learning force field. By adopting first-principles electronic structure calculations, we further revealed the charge transfer and active sites for both reactions in the identified heterojunction. Furthermore, assembling CMH cathode and Zn metal anode into a ZAB full-cell configuration achieves a ~5.5-fold higher energy density of 879 Wh kg-1 exceeding those of commercial lithium-ion batteries (LIBs), a high-discharge outstanding power density that is 1.39 times higher than novel metal catalysts, and robust cycle stability with negligible voltage decay which is far superior to that of benchmark Pt/C+RuO2 electrocatalysts.

Morphological engineering of PTAm@CNTs cathode for high-rate potassium dual-ion battery

Redox-active polymers are regarded as one of the most promising electroactive materials for non-lithium electrochemical energy storage devices due to the inherent molecular flexibility that can tolerate the structure change during the charge/discharge process. Their diverse functional groups provide abundant active sites to accommodate large-sized electrolyte ions. In this work, for the first time, the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical group, equipped at poly(TEMPO-acrylamide) (PTAm), is employed as an active cathode for potassium dual-ion batteries (KDIBs). Carbon nanotubes (CNTs) assist morphological engineering of the PTAm to create a conductive nanostructured composite, namely PTAm@CNTs. Systematic material characterizations and electrochemical evaluation suggest that the PTAm@CNTs nanocomposite possesses significant surface area and nanopores, enabling enhanced electronic and ionic conductivity. The PTAm@CNTs cathode reversibly stores hexafluorophosphate (PF6−) anions in KDIBs, delivering high energy density, rate capability, and robust cycling stability. The fast reaction kinetics of nitroxide radicals (N–O.), the redox-active groups on the PTAm, and their association with the PF6− anions contribute to the dual-ion storage. As a result, the PTAm@CNTs cathode delivers a high specific capacity of 108 mAh g−1 at 2 A g−1 (16.8C) over 300 cycles. The work suggests a promising pathway to design and synthesize functional organic electrode materials for potassium dual-ion batteries.

Facile electrodeposition of CoMn2O4 nanoparticles on nickel foam as an electrode material for supercapacitors

In this study, we successfully utilized nickel foam (NF) as a scaffold for the direct deposition of ultra-thin CoMn₂O₄ (CMOs) through a one-step electrochemical deposition method. This was followed by annealing to produce a stable, free-standing electrode. This electrode was then used to develop an aqueous asymmetric supercapacitor (AASC). The optimized electrode demonstrated an exceptionally high specific capacitance of 2218.32 F g−1 at 1 A g−1 and excellent cyclic stability, retaining 86.67 % of its capacitance after 6000 cycles. An AASC device was also constructed, employing CMOs on NF as the cathode and commercially available activated carbon (AC) on carbon cloth (CC) as the anode. This configuration achieved a high energy density of 83.85 Wh kg−1 at a power density of 800.03 W kg−1, with robust cycling stability (∼87.16 % retention after 16,000 cycles at 30.0 A g−1) and nearly 100 % Coulombic efficiency. These results surpass those of many state-of-the-art supercapacitors (SCs), highlighting the significant potential for practical applications.

"Lasagna"-Structured SnS-TaS2 Misfit Layered Sulfide for Capacitive and Robust Sodium-Ion Storage.

Stannous sulfide (SnS), a conversion-alloying type anode for sodium-ion batteries, is strong Na+ storage activity, a low voltage platform, and high theoretical capacity. However, grain pulverization induced by intolerable volume change and phase aggregation causes quick capacity degradation and unsatisfactory rate capability. Herein, a novel "lasagna" strategy is developed by embedding a SnS layer into the interlayer of an electrochemically robust and electron-active TaS2 to form a misfit layered (SnS)1.15TaS2 superlattice. For Na+ storage, the rationally designed (SnS)1.15TaS2 anode exhibits high specific capacity, excellent rate capability, and robust cycling stability (729 mAh cm-3 at 15 C after 2000 cycles). Moreover, the as-assembled (SnS)1.15TaS2 || Na3V2(PO4)3 full cells achieve robust and fast Na+ storage performance with ≈100% capacity retention after 650 cycles at 15 C, which also demonstrates good low-temperature performance at -20°C with a capacity retention of 75% and 2 C high-rate charge/discharge ability.

Tuning the microstructure of biomass-derived hard carbons by controlling the impurity removal process for enhanced Na ion storage performance

Biomass-derived hard carbons are promising anode materials of sodium-ion batteries (SIBs) due to their low cost, renewability and high specific capacity. However, there are inevitably some impurities in biomasses that may not only affect the purity, but microstructure and electrochemical performance of hard carbons. Although the impurities can be removed by appropriate treatments after carbonization, the microstructure of hard carbons can hardly be changed. In this work, taking ficus macrophylla leaves (FMLs) as the model biomass, the effects of impurities and their removing process on the microstructure and Na ion storage performance of hard carbons are investigated. It is found that the presence of Ca and Si-bearing impurities in FMLs results in more graphite-like structure in hard carbons because of their catalytic graphitization effect. The acid and base washing processes after carbonization can mostly get rid of the inorganic impurities is unable to increase the plateau region capacities associating to Na ion insertion in the interlayer of graphitic microcrystals and Na metal filling in micropores. By contrast, by stepwisely removing the Ca and Si-bearing impurities from raw materials before carbonization, hard carbons with high purity, larger interlayer space and more micropores are produced, which exhibit a high reversible specific capacity of 336 mAh g−1 at 20 mA g−1, a high initial Coulombic efficiency of 93 %, excellent rate capability (245 mAh g−1 at 2 A g−1) and robust cycle stability. This study implies that controlling the impurity removal process can simultaneously tune the microstructure of hard carbon anodes derived from biomasses towards high performance Na ion storage.

One-Step process of wrinkle microstructured iontronic pressure sensor with all fabric wearable electrode

The advancement of pressure sensors featuring high sensitivity, wide detection ranges, and linear response characteristics is important for advancing tactile sensing technologies for robots and human health monitoring. However, conventional preparation suffers from nonlinear signal output, non-environmental friendliness, and poor comfort, which affects the sensor’s ability to accurately detect different pressure levels, which is critical for subtle haptic feedback systems. To overcome these challenges, our research introduces a breakthrough in flexible capacitive pressure sensors by ingeniously integrating thermal stress-induced microstructured ionic gels with textile electrodes within a band-aid-like form factor. This method prevents the requirement for external templates or intricate manufacturing procedures, streamlining the production process while enhancing the sensor’s performance. The pivotal role of the ionic gel lies in its ability to form an efficient electric double layer (EDL), which adeptly transforms ion–electron interface interactions into measurable pressure-sensing outputs. Notably, this band-aid-based iontronic sensor showcases exceptional performance metrics. It exhibits an extraordinarily high sensitivity, reaching 5652.41 kPa−1, and demonstrates a broad pressure detection range (from 0-400 kPa). Additionally, the sensor responds rapidly to pressure changes, maintains robust long-term cycle stability, and boasts an impressively low detection threshold. Its potential applications, particularly in the precise monitoring of human muscle movements, open exciting new avenues for both health monitoring and the broader field of flexible electronic devices. This showcases the potential of everyday materials in advanced technological applications.

Marrying Fe nanoclusters with 3D carbon nanofiber aerogels: Triggering fast and robust faradic capacitive deionization

Faradic-capacitive deionization (FDI) has emerged promising research branch of capacitive deionization (CDI) to address the crisis in freshwater supply due to its high desalination capacity and unique ion storage mechanism over traditional CDI. However, the ion-storage mechanism of FDI imposes notable limitations on its desalination kinetics, while issues such as volumetric expansion (as well as the damage caused to the composite material’s structure) contribute to poor cycling stability. Herein, we developed a rational material design of Fe nanocluster-impregnated CNFAs (Fe NCs@CNFAs) and further used it as chloride-capturing electrode for FDI. This unique nanostructure not only provides fast surface-driven pseudo capacitance but also establishes a flexible scaffold that effectively protects the Fe NCs from severe morphology changes. As a result, our Fe NCs@CNFAs-based FDI exhibited both ultrahigh desalination capacity (120.38 mg g−1) and fast desalination rate (0.42 mg g−1 s−1), with robust cycling stability (showing only a 15.25 % decrease in desalination capacity after 100 cycles). This study underscores the significance of the problem-driven approach by leveraging soft scaffold-protected ultrasmall nanocluster to induce fast and durable desalination performance.