Cycling Stability Research Articles

Preparation of PU/SiO2 composite shell microencapsulated phase change materials with high thermal stability and thermal conductivity

To address the issues of poor thermal stability and thermal conductivity in polyurethane (PU) shell microencapsulated phase change materials (MEPCMs), this study prepared PU/SiO2-MEPCMs using an interfacial polymerization method combined with electrostatic self-assembly technology. First, the PU shell was synthesized via an interfacial polymerization reaction between isophorone diisocyanate (IPDI) and triethanolamine (TEA). Subsequently, the hydrolyzed product of tetraethyl orthosilicate (TEOS), monosilicic acid (Si (OH)4), was adsorbed onto the PU shell surface using electrostatic self-assembly technology and reacted with the –NCO groups to form an SiO2 shell. The effects of the PU/SiO2 composite shell on the surface morphology, chemical structure, compactness, thermal stability, phase transition performance, thermal conductivity, and thermal cycling stability of MEPCMs were investigated. The results showed that the formation of the PU/SiO2 composite shell significantly improved the thermal stability, compactness, thermal conductivity, and cyclic stability of MEPCMs. After continuous treatment at 150°C for 120 min, the leakage rate of the core material decreased from 12.13 % to 3.74 %, and the heat-resistant temperature (T95 %) increased by 30°C. Even after 1000 thermal cycles, MEPCMs still exhibited excellent heat storage performance. Additionally, even under high temperature conditions of 257°C (where pure butyl stearate completely decomposes), the PU/SiO2-MEPCMs still maintained a stable core-shell structure. The introduction of the SiO2 shell greatly enhanced the thermal conductivity of MEPCMs, aligning the phase change temperature more closely with that of the core material and effectively reducing the supercooling phenomenon. Furthermore, the stable energy storage system formed by MEPCMs on the finished fabric surface can endow it with excellent temperature regulation functionality.

Zein protein-functionalized separator through a viable method for trapping polysulfides and regulating ion transport in Li[sbnd]S batteries

Commercialization of lithium‑sulfur (LiS) batteries as a promising energy storage system, is primarily impeded by polysulfide shuttling and uncontrollable lithium dendrite growth. To address the issues for improving the performance of LiS batteries, we decorate the separator with zein (corn protein) via a simple soaking process. Owing to strong zein–polysulfide interactions, the zein-soaked separator effectively enhances the polysulfide-trapping capability. Moreover, abundant functional groups of zein also stabilize Li-ion deposition, and thus suppresses the growth of Li dendrites. As a result, the resulting LiS batteries exhibited enhanced electrochemical performance in terms of cycling stability, capacity retention, and rate capability. The soaking method used for coating zein on pristine separator offers a scalable solution for generating multifunctional separators toward commercialization.

Surface engineering of TiSiO4 nano-coating for high-voltage nickel-rich ternary cathodes: An approach to improve cyclic performance

In recent years, layered ternary transition metal oxides with a high nickel content have gained substantial attention as a potential positive electrode material for lithium-ion batteries. However, its poor rate capability, cyclability, and capacity retention at high working voltages limit its use in commercial lithium-ion batteries. To overcome these challenges, we synthesize a cost-effective wet-chemical deposition of novel TiSiO4 nano-coatings over the surface of LiNi0.83Mn0.06Co0.11O2 (NMC-83). X-ray diffraction and electron microscopy confirm the presence of a coating and verify that the deposition process did not alter the crystallinity and morphology of the NMC-83 particles. In addition, during cycling, it completely protects NMC-83 with enhancements in hexagonal phase transitions between H2 and H3, resulting in excellent cycling stability at upper cut-off voltages. Likewise, when the amount of coated material is equal to 1 wt%, it provides faster ion kinetics and a stable electrode-electrolyte interface. The 1 wt% TiSiO4 coating provides 35 % retention after 250 cycles at a 0.5C rate, while the pristine NMC-83 shows only 13.7 %. From postmortem analysis, the 1 wt% TiSiO4-coated NMC-83 cathode maintains its stable polycrystalline nature compared with pristine NMC-83. Thus, this novel TiSiO4 nanocoating has significant implications for developing high-performance rechargeable batteries for energy applications.

Electrospun metal-organic framework materials derived bimetallic oxides as high-efficiency anodes for lithium-ion battery

Energy devices are receiving more and more attention, and this is especially true for lithium-ion batteries. Moreover, applying novel nanostructures in multicomponent systems is a very effective way to promote the development of energy storage systems. This study synthesizes a nitrogen-doped carbon nanofiber encapsulating MOF-derived bimetallic oxide nanomaterial by combining electrospinning and MOF materials. Nitrogen-doped carbon nanofibers are porous and highly conductive, providing structural stability, a practical pathway for lithium ion diffusion, and an essential channel for rapid charge transfer during cycling. The bimetallic oxides derived from the MOF materials provide sufficient space for fast reaction sites and mitigate volume expansion during cycling. When the composite material FNO@NCNFs is used as the anode material for lithium batteries, its reversible capacity is maintained at 1105.4 mAh g−1 after 100 cycles at a current density of 0.1 A g−1. Its capacity reaches 748.5 mAh g−1 after 900 cycles at a current density of 1 A g−1, and at the same time, it exhibits excellent cycling stability, with the coulombic efficiency remaining above 98 %. The material also exhibits a small ion transfer resistance and good rate performance. The structural design approach based on combining MOFs with electrospinning in this study will provide new insights into the design and development of materials for advanced energy storage applications.

Multi-dimensional carbon modification strategy for lithium-ion battery anodes: Carbon-covered TiP2O7 supported by 3D carbon skeleton

Carbon coating is a beneficial method for improving surface capacitive behavior, electron transfer kinetics and cyclic stability of three-dimensional lattice lithium-embedded anode materials. Herein, we adopt one-step pyrolysis to achieve carbon-covered TiP2O7 supported by a three-dimensional carbon skeleton utilizing phytic acid and glucose as carbon sources. The two-dimensional amorphous carbon layer on TiP2O7 surface improves the initial Coulombic efficiency and rate capacity by inhibiting the irreversible embedding of lithium ions and reducing the interfacial charge transfer impedance. The three-dimensional carbon skeleton not only forms a conductive pathway between the carbon-covered TiP2O7, but also its large specific surface area, randomly oriented and defective carbon layer provide extra lithium storage sites and capacitive contribution. In addition, the specific capacity of the TiP2O7/C composite is still as high as 314.5 mA h g−1 after 1000 cycles at 1 A g−1. A TiP2O7/C//LiFePO4 full cell delivers a high energy density of 273.96 Wh kg−1 at 0.153 kW kg−1, and retains 114.43 Wh kg−1 even at the power density of 4.086 kW kg−1. The multi-dimensional carbon modification strategy has improved the electrochemical performance of TiP2O7-based anode materials, providing a model for synthesizing other high-performance anode materials.

Reconstructing Electrically Conductive Nanofiltration Membranes with an Aniline-Functionalized Carbon Nanotubes Interlayer for Highly Effective Toxic Organic Treatment.

Conductive nanofiltration (CNF) membranes hold great promise for removing small organic pollutants from water through enhanced Donnan exclusion and electrocatalytic degradation. However, current CNF membranes face limitations in conductivity, structural stability, and nanochannel control strategies. This work addresses these challenges by introducing aniline-functionalized carbon nanotubes (NH2-CNTs) as an interlayer. NH2-CNTs enhance the dispersibility and adhesion of pristine carbon nanotubes, leading to a more conductive and stable composite nanofiltration membrane. The redesigned NH2-CNTs interlayered conductive nanofiltration (NICNF) membrane exhibits a 10-fold increase in conductivity and a high response degree (80%) with excellent cyclic stability, surpassing existing CNF membranes. The synergistic effects of enhanced Donnan exclusion, voltage switching, and electrocatalysis enable the NICNF membrane to achieve selective recovery of mixed dyes, 98.97% removal of residual wastewater toxicity, and a 5.2-fold increase in permeance compared to the commercial NF270 membrane. This research paves the way for next-generation multifunctional membranes capable of the efficient recovery and degradation of toxic organic pollutants in wastewater.

Free-standing snowflake-like Mn-doped ZnO@CoCo2O4 nanofilm boosting cycle stability and energy density of supercapacitor

CoCo2O4 is considered as one of the most promising electrode materials owing to its inherently electrochemical performance and low cost. Nevertheless, the further practical application of CoCo2O4 as high-performance electrode material is hindered by its weak cycle stability. Herein, a free-standing snowflake-like Mn-doped ZnO@CoCo2O4 (MZCC) nanofilm is synthesized via hydrothermal method. The unique snowflake structure of this nanofilm composite exhibits obviously large specific surface area, thus promoting the redox reaction of the electrode material. The specific capacitance of the MZCC attains 1245F g−1 at 0.5 A/g. Furthermore, the assembled supercapacitor device with the MZCC and active carbon shows an energy density of 25.7 Wh kg−1 at a power density of 400 W kg−1. The device also demonstrated intriguingly outstanding cyclic stability, maintaining its original specific capacitance of 80.1 % after 3000 cycles at 2 A/g. This study delivers an effective method to construct high-performance free-standing metal oxide nanofilm electrodes for advanced supercapacitors.

Carbon coating engineering enhances the stability of graphite anode in potassium ion batteries

Graphite forms reversible potassium-graphite intercalation compounds electrochemically. Graphite anode possesses a high reversible specific capacity (279 mAh g−1) and an optimal low potential platform, rendering it an ideal anode material for potassium-ion batteries. However, the intercalation of K+ ions in graphite causes a bulk volume expansion of up to 61%, resulting in irreversible damage to the structure of graphite, which leads to inferior cycling stability. In this paper, surface-oxidized graphite (OG) with reduced particle size and increased defect densities was obtained by mechanical ball milling and chemical oxidation. Composites of soft carbon-coated OG (OG@PC) were prepared by soft carbon coating. The soft carbon coating can alleviate the bulk expansion caused by K+ intercalation/deintercalation in OG, thus slowing down the destruction of the crystalline structure of graphite after multiple charging/discharging cycles. OG@PC exhibits increased reversible specific capacity from 267 mAh g−1 to 314 mAh g−1 compared with pristine graphite at a current density of 0.05 A g−1. Moreover, at a high current density of 0.5 A g−1, a reversible specific capacity of 213 mAh g−1 was achieved after 200 cycles. This work investigates simple surface carbon coating strategies to improve the cycling stability of a graphite anode of potassium-ion batteries.

Efficient unsymmetric disulfide formation by molecular-scale tailoring of ortho-polyquinone-based polymer photocatalyst

Disulfide bonds, especially unsymmetric disulfide bonds, have important applications in bioactivity and drug molecules, but the synthesis of unsymmetric disulfide bonds remains challenging due to efficiency and selectivity issues. Herein, this work utilizes anthraquinone (AQ) and cyclictriphosphonononitrile through a nucleophilic substitution reaction to synthesize an organic polymer (ANTH-AMI) that incorporates an ortho-polyquinone (o-polyquinone) redox center. The anthraquinone molecule functions as a redox center, capable of accepting photoinduced electrons and subsequently transferring them to initiate an electron-coupled hydrogenation reaction (AQ to AQH). Moreover, the proximity of the o-polyquinone redox sites facilitates the catalysis of unsymmetric disulfide bond formation. Consequently, the ANTH-AMI photocatalysts demonstrate exceptional yields (up to 82 %), substrate versatility, cycling stability, and scalable preparation in promoting unsymmetric coupling reactions of thiol. This work offers a solution for designing organic polymer photocatalysts with adjacent multiple redox centers for cross-coupling reactions.

Li1.4Al0.4Ti1.6(PO4)3 coating surface modification enables improved electrochemical performance of LiNi0.83Co0.11Mn0.06O2 cathode

High-nickel ternary active materials with LiNi0.83Co0.11Mn0.06O2 (NCM83) have attracted extensive attention from researchers because of their exceptional performance and competitive pricing. Nevertheless, the actual large-scale uses of this material are restricted due to its limited lithium vacancies, residual lithium on the surface, and poor thermal stability. To improve the electrochemical performance of NCM83, an effective strategy for coating high ionic conductors of Li1.4Al0.4Ti1.6(PO4)3 (LATP) on NCM83 has been proposed. The uniform coatings of LATP are prepared by a wet coating process, which efficiently protects NCM83 from electrolyte attack, reduces internal stress, and improves the material’s thermal stability. Consequently, the cycle stability and thermal stability of the coated cathodes are significantly enhanced. Typically, 1 wt% LATP coating delivers a higher discharge specific capacity of 179.3 mAh g−1 at 2 C. The capacity retention rate is 69.67 % after 300 cycles at 1 C, higher than NCM83 (capacity retention rate of only 61.27 %). This study presents a new direction for researching high-nickel ternary cathode materials.

MoS2@Ti3C2Tx Heterostructure: A new negative electrode material for Li-Ion hybrid supercapacitors

Lithium-ion hybrid supercapacitors (LHSCs) demonstrate promising electrochemical performance, including long cyclic stability and a high-power density. However, their limited energy density has restricted the development towards commercialization. In this work, a novel heterostructure (HS) has been introduced based on molybdenum disulfide (MoS2) nanosheets (NSs) anchored on the surface of exfoliated layers of titanium carbide (Ti3C2Tx) MXenes. The prepared negative electrode material named as MoS2@Ti3C2Tx–HS holds substantial promise for advancing LHSCs to enhance energy density. The MoS2@Ti3C2Tx–HS demonstrates outstanding pseudocapacitive performance in a three-electrode system by achieving a capacitance of 1022.7 F g−1 at 1 A g−1. It exhibited a stable cyclic life (5,000 cycles) and retained 97.02 % of its initial capacitance. Theoretical calculations based on density functional theory (DFT) show impressive results to support the experimental work. The calculated density of states (DOS), band structures, adsorption energies (Eads), and diffusion energy demonstrate that MoS2@Ti3C2Tx–HS possesses excellent electronic and adsorption properties. The fabricated MoS2@Ti3C2Tx–HS//CP–LHSCs device shows a high capacitance of 153.75 F g−1 at 2 A g−1, with stable cyclic life (94.5 %) over 10,000 cycles. Furthermore, it shows a notable high energy density of 54.7 Wh kg−1 at a power density of 1,601.3 W kg−1. The prepared MoS2@Ti3C2Tx–HS electrode, with its synergistic combination, stands out as an auspicious material, showing remarkable electrochemical performance and paving the way for LHSCs.

Defect-driven ion storage on hexagonal boron nitride for fire-safe and high-performance lithium-ion batteries

The mass market adoption of electric vehicles has increased the risk of safety concerns, such as overheating and flammability. Rational design of fire-safe and high-capacity anodes with thermal tolerance, capable of fast-charging and long cycle-life, is crucial for the development of next generation Li-ion batteries operating under extreme conditions. Here we report a defect engineered hexagonal boron nitride (hBN) anode to mediate the safety dilemma. We demonstrate that the defects generated via cryomilling catalyze the reversible LiF formation and enable the pseudocapacitive type Li-ion storage on hBN. The non-flammability and excellent thermal tolerance of hBN allows high specific capacity (880 mAh/g @ 25 mA/g), rate performance (480 mAh/g @ 5 A/g) and stable cycling (5000 cycles) at 60 °C. The Li-ion full-cell with the defective hBN anode and the conventional cathode (LiNiMnCoO2) delivers significantly higher energy (400 Wh kg−1) and power density (1 kW kg−1) when compared to graphite/LiNiMnCoO2 full-cells (121 Wh kg−1 and 250 W kg−1). First-principles calculations confirm that nitrogen antisite (NBVN) defects are responsible for the electrochemical activation of otherwise inactive hBN. The strategy of defect-induced electrochemical activation opens up new avenues in the design of high-performance electrode materials for numerous secondary batteries.

Preparation and photocatalytic mechanism of magnetic Ag2S/CoFe1.95Dy0.05O4 Z‐scheme heterojunction

AbstractThe synthesis of high‐efficiency magnetic composite photocatalyst by doping magnetic cobalt ferrite and compounding single semiconductor photocatalyst is a promising strategy to improve the oxidation ability of photocatalytic systems. In this paper, CoFe1.95Dy0.05O4 (CFDO) was prepared by doping Dy element into magnetic CoFe2O4, and Ag2S (AS)/CFDO with high‐efficiency magnetic photocatalyst was synthesized by compounding AS with CFDO as the substrate. The photocatalytic samples were characterized by different advanced characterization methods, and their photocatalytic degradation of methylene blue (MB) was studied. The results show that AS/CFDO exhibits higher visible light response, excellent photogenerated charge separation ability and migration efficiency, and excellent catalytic performance in the catalytic degradation system. The photocatalytic activity of AS/CFDO was the highest, and its photocatalytic degradation kinetic constant K was 2.48 and 1.54 times that of AS and CFDO, respectively. In addition, the catalyst contained in the catalytically contaminated solution can be effectively separated by an external magnetic field to achieve multiple cycles of degradation and recycling. The cyclic degradation experiments showed that AS/CFDO exhibited high degradation stability during the photodegradation process. After the fifth reuse, the degradation efficiency was still more than 88.0%. Finally, the possible photocatalytic mechanism of the samples was discussed. Therefore, this work provides an effective solution for the construction of photocatalysts with high efficiency, magnetic recovery, and cyclic degradation stability and avoids the secondary pollution of catalysts to organic wastewater. It is of great significance to create an environmentally friendly catalytic method for efficient cyclic degradation of organic wastewater.

Tailoring the grain boundary structure and chemistry of the dendrite-free garnet solid electrolyte Li6.1Ga0.3La3Zr2O12

Garnet-type Li6.1Ga0.3La3Zr2O12 (LGLZO) exhibits high ionic conductivity and extremely low electronic conductivity. The electrochemical properties strongly depend on the characteristics of the grain boundaries and pores in the oxide–ceramic electrolyte. Currently, the main issue of LGLZO is its large grain boundary resistance due to high-temperature sintering. Herein, we propose an effective method for reinforcing the chemical and structural characteristics of the grain boundaries using a Li2O-B2O3-Al2O3 (LBA) sintering aid. In this study, the LBA sintering aid is critical because it fills grain boundaries and void spaces. As a result, LGLZO solid-state electrolytes with sintering aids significantly enhance the ionic conductivity and reduce the activation energy, especially in the grain boundary region. Another crucial issue is the formation of Li dendrites in LGLZO. Since dendritic Li propagates along the grain boundaries, the optimized LGLZO solid-state electrolyte demonstrates excellent stability against Li metals. Overall, the LGLZO electrolyte with the LBA sintering aid exhibits stable long-term cycling performance due to the well-designed grain boundaries.

Eliminating Hydrogen Fluoride through Piperidine-Doped Separators for Stable Li Metal Batteries with Nickel-Rich Cathodes.

Hydrofluoric acid (HF)-induced electrode and interfacial structure degeneration poses a significant challenge for high-voltage lithium metal batteries (LMBs). To address this issue, we propose a separator strategy that involves decorating a regular polyethylene (PE) separator with molecular sieves (TW) impregnated with piperidine (PI). The porous structure of the TW serves as a reaction chamber for PI and HF. As a result, the HF content in the controlled electrolyte with 500 ppm H2O (ELE-500) is notably reduced when using TW@PI-PE separators, thereby shielding nickel-rich cathodes from HF etching. Simultaneously, due to the hydrolysis of Li salts, and the inertness of PI towards H2O, a uniform lithium fluoride (LiF)-rich solid electrolyte interphase can form on the Li metal anode, further mitigating dendrite formation. The lifespan of the symmetric Li cell using the TW@PI-PE separator is doubled in ELE-500, exhibiting stable 500-hour cycles at 3 mA cm-2 and 3 mAh cm-2. Additionally, with the effective limitation of transition metal (TM) dissolution, the 4.6-V LMBs employing a LiNi0.8Co0.1Mn0.1O2 cathode maintain an 81% capacity retention over 100 cycles, even in ELE-1000. The innovative TW@PI system presented here offers a fresh perspective for future research aimed at eliminating HF in LMBs.

Controllable Synthesis and Growth Mechanism of Cracked Cowpea-Like NCNT Encapsulated with Fe3N Nanoparticles for High-Performance Anode Material in Lithium-Ion Batteries

Fe3N nanocrystals embedded in cracked N-doped carbon nanotubes (Fe3N@NCNT) with a cowpea-like shape are innovatively prepared by metal-catalyzed graphitization and nitridization processes based on melamine and FeC2O4 precursor. The new in-situ synthesis strategy is proved to be effective to open the NCNT using a migratory metal carbide nanocatalyst via expansion effect and fabricate a metal nitride embedded NCNT with fully active ingredients. The detailed tip-growth mechanism of cracked NCNT with latitudinal-longitudinal graphene layers is studied by in-situ XRD analysis of the phase evolution of melamine and FeC2O4, and ex-situ SEM/TEM investigation of the topography correlation of NCNT and Fe3C floating catalyst. The Fe3N@NCNT microclews based anodes have a moderate carbon content of 35.45 wt%, electroactive NCNT conductive network, abundant microcracks and an open short-cavity system, showing a stable discharge capacity of 667 mAh g−1 at 0.1C, outstanding rate capability of 448 mAh g−1 at 5C and remarkable long-term cycling stability of 546 mAh g−1 after 600 cycles at 1C. The combined good electronic/ionic conductivity of cracked NCNT and robust mechanical stability of geometrically confined Fe3N nanoparticles contribute to the excellent redox activities, stabilized solid-electrolyte-interphase film and cycling durability of Fe3N@NCNT.

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.

Anchoration of hydrothermally developed FeSe nanoparticles on rGO nanosheets as electrode for energy storage devices

A perpetual discrepancy exists between demand and supply due to the inherent fluctuation of renewable energy sources. A possible approach for addressing this persistent issue involves the advancement of appropriate materials for consumption in energy storage systems. An example of a device that can potentially serve as energy storage is a supercapacitor equipped with highly effective electrode materials. This study synthesizes FeSe, rGO and FeSe@rGO electrodes via hydrothermal route. Specific capacitance (Cs) of FeSe, rGO and FeSe@rGO electrode was measured by GCD analysis as 517, 799, and 1408 F g−1 at 1 A g−1. The synthesized FeSe@rGO nanohybrid exhibits outstanding performance and high cycling stability up to 10000th cycles. Furthermore, the enhanced supercapacitance of the nanohybrid has been ascribed to the synergistic interaction between FeSe and rGO, which delivers higher surface area and enhanced active sites. Further, symmetric two-electrode study revealed excellent electrode material with specific capacitance (Cs) of 553 at 1 A g−1 with capacitive retention of 66.36 % after 1000th cycle. However, the electrochemical investigation demonstrated that the FeSe@rGO nanohybrid structure exhibited superior performance and could be used in different electrochemical applications.

Electrochromic behaviors and applications of tetrasubstituted thienoviologen derivatives

Electrochromic materials have been widely used in various parts of life due to their advantages of energy conservation and rich colors. In this work, a series of novel viologen derivatives (tetrasubstituted thienoviologen derivatives, a–f) were designed and synthesized as electrochromic materials by decorating 4,4′,4″,4‴-(thiophene-2,3,4,5-tetrayl)tetrapyridine with different N-substituents (alkyl, benzyl and aryl). Electrochromic devices based on a–f exhibited a low working voltage of −1.4 V. The N-substituents markedly affected their electrochromic performance. The compounds with alkyl and benzyl substituents performed better than the compound with aryl substituent. Among them, compound c with benzyl substituent performed best with a high optical contrast (66 %), a high coloration efficiency (389 cm2/C), good cycling stability, and fast response time. Besides, compound c was also applicable to sodium carboxymethyl cellulose hydrogel ECD with good cycling stability and a broad absorption band (500–700 nm) in the visible region. The applications of compound c in electronic tags, functional displays and smart windows were explored, indicating it's a promising ECM with wide application prospects.

Prolonging rechargeable aluminum batteries life with flexible ceramic separator

Rechargeable aluminum batteries (RABs) are attracting significant attention for their high theoretical capacity and abundant reserves. However, the poor mechanical performance of glass fiber (GF) separators and the formation of Al dendrite severely hinder the practical cycle life of these batteries. Herein, a flexible ceramic separator was developed with simple coating technique, effectively improving the cycling stability of RABs. Compared with the commercial GF separator, this flexible ceramic separator has less thickness and superior electrolyte wettability, resulting in improved interfacial compatibility and minimized interfacial resistance. Moreover, its exceptional flexibility and toughness (stress of 39.34 MPa) coupled with uniform nanopore structure, which can effectively resist the penetration of dendrites. As expected, this ceramic flexible separator facilitates stable cycling of the symmetric battery for over 1762 h at 2 mA/cm2 and 2 mAh/cm2. It also permits the pouch Al//flake graphite full battery to achieve a coulombic efficiency of up to 90% even after 115 cycles. Apparently, this work developed the simple separator manufacturing strategy that provides an effective method to improve the cycling stability of RABs and extends the application to other types of batteries.