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• Highly hydrophilic and underwater superolephobic PVDF membrane was prepared. • The as-prepared PVDF membrane shows efficiencies higher than 99.4 % in various emulsion separations. • The as-prepared PVDF membrane exhibits recyclable oil/water separation performance. • The proposed one-step solution-immersion method based on catechol and polyamines is facile, eco-friendly and low-cost. In this study, poly(vinylidene fluoride) (PVDF) microfiltration membrane was modified by an eco-friendly and low-cost mussel-inspired method for applications in oil/water separation. Catechol (CA) and polyamines, instead of dopamine (DA), were utilized to modify the membranes based on a facile one-step solution-immersion process. Similar to the oxidation polymerization of DA, polyamines can react with CA via Schiff base/Michael addition reaction. A homogeneous coating with micro-nano structures and superior hydrophilicity can be formed on the surface of the membrane and the inner walls of its holes. The membrane with a water contact angle of nearly 0° and a water flux above 8000 L/m2 h was obtained after being modified with 5 mM CA and tetraethylene pentaamine (TEPA) for 24 h. The micro-nano scale roughness and the superior hydrophilicity contributed to an excellent underwater superoleophobicity with oil contact angles larger than 150° and low adhesion to various oils. The as-prepared membrane was applied to separate a series of oil-in-water emulsions, and a high separation efficiency larger than 99.4 % as well as extraordinary antifouling property without discernible decay after ten cycle tests were demonstrated. Moreover, the functional coating shows good stability in acid and alkali environment with the pH values between 0 and 11, and has few impacts on the mechanical and thermal properties of the pristine membrane. Therefore, the proposed facile and low-cost preparation of the underwater superoleophobic microfiltration membrane shows great potential in practical oily wastewater treatment. [ABSTRACT FROM AUTHOR]

Cyclization reaction of poly(acrylonitrile-co-2-acrylamido-2-methylpropane sulfonic acid) [P(AN-co-AMPS)] copolymer during thermal oxidative stabilization (TOS) process was investigated by FTIR and two dimensional (2D) correlation analysis technique. The results showed the mechanism of cyclization reaction at different temperatures were varying. At 200 °C, the cyclization reactions generated by autocatalytic cyclization mechanism. While at higher temperatures, the cyclization reactions took place through ionic cyclization mechanism and free radical cyclization mechanism. The AMPS comonomer could reduce the heat release of cyclization reactions and improve the stability at 200 and 230 °C. At higher temperatures, the cyclization reactions were facilitated rapidly. However, the oxidation and degradation reactions were also intense, which will cause the molecular chain to break and defects in the final carbon fibers (CFs). This research has theoretical guiding significance for the optimization of heat treatment conditions for PAN copolymers used as CFs. • The cyclization mechanism of P(AN-co-AMPS) copolymer was verified by in-situ FTIR and 2D correlation analysis. • The mechanism of cyclization reaction of P(AN-co-AMPS) copolymer at different temperatures were varying. • The cyclization reactions generated by autocatalytic cyclization mechanism at 200 °C. • The cyclization reactions generated via ionic cyclization and free radical cyclization mechanism at higher temperatures. • The AMPS comonomer could reduce the heat release of cyclization reactions and improve the stability during TOS process. [ABSTRACT FROM AUTHOR]

• A facial emulsion assistant method allows the synthesis of hybrid xerogels. • Hybrid xerogels directly obtained by ambient pressure drying. • The MHXs xerogels exhibit large porosity and low thermal conductivity. • The MHXs xerogels can bear a compression load of up to 50 MPa. • The whole preparation process is economical and environment-friendly. In this study, we report a convenient one-pot synthesis of silsesquioxane hybrid xerogels with excellent mechanical flexibility by using copolymer emulsion as templates. During the acid-catalyzed sol-gel process of the precursors, the random copolymers of n-butyl methacrylate (n-BMA) and hydroxyethyl methacrylate (HEMA), not only suppressed macroscopic phase separation but also were incorporated in the skeleton of polysilsesquioxane by synergistic physical and chemical interactions. The resultant gels could be directly dried via ambient-pressure drying (APD) to gain xerogels without visible volume shrinkage. This unique preparation process is economical and environment-friendly without involving any organic solvents. The morphology and physicochemical performance of the monolithic hybrid xerogels can be readily tailored by changing the compositions and the concentrations of silsesquioxanes and copolymers in the reaction solutions. Xerogels fabricated from methyltrimethoxysilane showed excellent thermal insulation property, inherently superhydrophobicity, and outstanding mechanical strength against compression up to 50 MPa. Besides, the compressed specimen could recover its original shape by immersing in solvents and subsequently drying. [ABSTRACT FROM AUTHOR]

The composite solid electrolytes (CSEs) inherits the high safety of the inorganic solid electrolyte and the easy processing of the organic polymer electrolyte, thereby exhibiting a broad application prospect. However, the performance of the CSE was hard to realizing its practical application in lithium metal batteries. Herein, the significant impact of CSE performance brought about by the addition of ionic liquids was studied and summarized: significantly increase ionic conductivity; constructing a viscoelastic interface between electrode and electrolyte to reduce the interface impedance; forming a stable and LiF-rich SEI at the negative electrode to inhibit the growth of lithium dendrites; wetting the LiFePO 4 porous cathode. The LiFePO 4 /CSE-60/Li battery displays high initial discharge specific capacity of 158.2 mAh g−1 and a capacity retention of 86.3% after 400 cycles at 1 C at 55 °C, and with coulombic efficiency of 99.7%. The surface of the lithium metal anode after long-term cycling exhibits to dendrite-free morphology. This research highlights the critical role that ionic liquids play in improving the performance of CSEs and will shed light on designing CSEs for LMB practical applications. • Ionic liquid enhanced composite solid electrolytes. • Realizing practical applications of CSEs in lithium metal batteries. • The critical role that ionic liquids play in improving the performance of CSEs. [ABSTRACT FROM AUTHOR]

• A 2D MXene wrapped Ni-Fe oxide nanocube based flexible electrode was synthesized. • The composite film functioned like a mixed analogous heterostructure. • The film successfully combined the advantages of different components. • The film demonstrated satisfied electrochemical performance and flexibility. In this work, we addresses the fabrication of a flexible film electrode based on 2D MXene wrapped 3D Ni-Fe oxide nanocube mixed analogous heterostructure. The resulted composite film electrode successfully inherits the merit of different building blocks: MXene layers works as binders and conductive additives that can connect cubic Ni-Fe oxide nanoparticals, facilitate the charge transfer and avoid a significant conductivity decrease in the resulting electrode. While cubic Ni-Fe oxide serves as an active spacer inside the adjacent MXene layers to increase the interlayer space, facilitate the electrolyte diffusion and enhance the electrochemical activity of the composite film. As a result, the optimized composite film manifests excellent specific capacitance of 1038.43 mF cm−2 at current density 0.5 mA cm−2. Meanwhile by assembling into all-solid-state flexible supercapacitor, an excellent specific areal capacitance of 328.35 mF cm−2 at 0.2 mA cm−2 was achieved. Additionally, the excellent energy storage performance is well maintained with a capacitance retention of 90.9% during 10,000 charging-discharging long cycles. Furthermore, a high mechanical robustness with 88.9% capacitance remained after subjected to bending at 90° for 50 cycles, suggesting great potentials for the applications in future flexible and wearable devices. [ABSTRACT FROM AUTHOR]

• C O groups on the modified cathode enhanced the peroxymonosulfate activation. • 1O 2 and SO 4 − played an important role in the ofloxacin degradation. • Activation mechanism of peroxymonosulfate at the cathode was proposed. • The degradation pathway of ofloxacin was identified. This study described a promising photoelectrocatalytic (PEC) system enhanced by peroxymonosulfate (PMS) for the treatment of ofloxacin in wastewater. The PEC system, which employed a BiVO 4 as photoanode and a polydopamine modified carbon felt (PDA/CF) as cathode, was constructed. The PDA/CF cathode was easily prepared by a dopamine self-polymerization process. The effect of PMS concentrations, applied potential and initial solution pH on the ofloxacin degradation was investigated in the enhanced PEC system. Ofloxacin can be completely removed after 120 min reaction under the optimal conditions of applied potential 1.5 V, pH 5.0 and 2 mM PMS addition. Based on the electron spin resonance measurement, sulfate radicals (SO 4 −), hydroxyl radicals (OH) and singlet oxygen (1O 2) were mainly responsible for ofloxacin degradation. Analyses of the degradation intermediates indicated that the C N bond, piperazine ring and the fluoride group of ofloxacin were attacked in its degradation process. The introduction of dopamine on the cathode significantly enhanced the PMS activation to produce active radicals, which further improved the ofloxacin degradation. The possible mechanism was proposed for ofloxacin degradation in the PEC system enhanced by the addition of PMS. [ABSTRACT FROM AUTHOR]

The morphology evolution process of g-C 3 N 4 -TSH with increase of the temperature. • Thin-shelled honeycomb-like structured g-C 3 N 4 was prepared by simple one-step way. • Proportion of melamine/NH 4 Cl and pyrolysis temperature affected the formation process. • Morphology evolution mechanism was revealed systematically during g-C 3 N 4 formation. • It is conducive to design dimension oriented g-C 3 N 4 structures via solid-state chemistry. • The prepared 3-D g-C 3 N 4 showed remarkable photoactivity for H 2 evolution from H 2 O. Synthesis of three-dimensional carbon nitride (g-C 3 N 4) structures is a promising but challenging task for effectively photocatalytic water splitting to generate H 2. In this study, thin-shelled honeycomb-like structured g-C 3 N 4 (g-C 3 N 4 -TSH) was successfully synthesized via facile one-step co-pyrolysis of melamine/NH 4 Cl mixture and the morphology evolution mechanism was revealed systematically. By varying the ratios of melamine/NH 4 Cl precursor and thermal preparation temperatures, thin-shelled and thick-shelled honeycomb-like structured g-C 3 N 4 were obtained. Also, the key intermediate phases were identified by their structure characterizations, which revealed low-temperature phase transition of 1-D tube-like melamium/NH 4 Cl adduct, then transforming to 2-D multiple plate-like melamium/melon NH 4 Cl complex by sintering, and finally evolving to g-C 3 N 4 -TSH at high temperature. The final hierarchical structure has several beneficial features as hollow, mesoporous, ultrathin, and honeycomb-like form, which caused its high surface area, excellent mass transfer rate and good light absorption ability. As a result, the g-C 3 N 4 -TSH with Pt as co-catalyst showed remarkable photoactivity for H 2 evolution, with an apparent quantum efficiency of 9.86% at 420 ± 10 nm, which is superior to many reported modified g-C 3 N 4. This study revealed the evolution mechanism of g-C 3 N 4 -TSH, which is conducive to design various dimension oriented g-C 3 N 4 structures via solid-state chemistry for photocatalytic H 2 evolution. [ABSTRACT FROM AUTHOR]

• Zn0 reduction and Fenton oxidation was innovatively combined to remove BDE47. • Surfactant-assisted Zn0 as active reductant was used for the debromination of PBDEs. • Low-brominated PBDEs from reduction was rapidly decomposed by Fenton reagent. • The combination of reduction and oxidation possessed the obvious cost effectiveness. • Mechanistic detail of BDE47 degradation in the combination process was proposed. 2,2′,4,4′-tetrabromodiphenyl ether (BDE47) was difficult to be rapidly degraded by common reductive debromination or oxidative decomposition. In this study, the debromination via surfactant-assisted zero valent zinc (Zn0) reduction and subsequent Fenton oxidation was combined to completely degrade BDE47. Firstly, Zn0 integrated with surfactants including cetyltrimethylammonium chloride (CTAC), polyethylene glycol dodecyl ether (Brij35), or 1-dodecanesulfonic acid sodium salt (SDS) were evaluated for their reactivity to debrominate BDE47. CTAC-assisted Zn0 system presented the highest removal efficiency of 98.6% for BDE47 (C 0 = 5 mg/L) under the optimized conditions including 0.3 g/L of Zn0 particles and 0.05 g/L of CTAC at 25 °C and pH 4.0 during 1-h reaction. Subsequently, the debromination products as low-brominated BDEs were attacked by hydroxyl radicals (•OH) from Fenton reagent, which were decomposed into short-chain carboxylic acids and even mineralized within 2-h oxidation. In addition, HPLC, GC–MS, LC–MS/MS, and IC were employed to detect intermediates during this reaction/oxidation process and the pathways of debromination and oxidation were proposed according to carbon and bromine balance. The above combination achieved the complete degradation of BDE47 via a relative low-cost method to rapidly remove PBDEs, which provide a new approach for the effective treatment of halogenated organic pollutants. [ABSTRACT FROM AUTHOR]

Novel p-n heterojunction designed MoS 2 –g-C 3 N 4 /Ni 2 P catalyst for solar hydrogen generation. • MoS 2 is innovatively combined with g-C 3 N 4 loaded by Ni 2 P for solar hydrogen generation. • High hydrogen generation rate was achieved by this environmentally benign photocatalyst. • The composite of MoS 2 nanosheets and g-C 3 N 4 /Ni 2 P was prepared by simple annealing process. • 2D MoS 2 –g-C 3 N 4 p-n heterojunction efficiently promoted the electron-hole pair separation. • Ni 2 P as low-cost synergist could significantly accelerate the hydrogen reduction process. Solar energy conversion by photocatalytic hydrogen generation provides a clean alternative to fossil fuels. However, designing more efficient, chemically stable and affordable catalytic systems remains a great challenge for industrial application. In this study, p-type MoS 2 is innovatively introduced on the n-type g-C 3 N 4 loaded with Ni 2 P, which forms a new earth-abundant and environmentally benign photocatalyst for solar hydrogen generation. Firstly, we prepared the ternary MoS 2 –g-C 3 N 4 /Ni 2 P composite by ultrasonically mixing MoS 2 nanosheets with g-C 3 N 4 /Ni 2 P by simple annealing process. The as-synthesized MoS 2 –g-C 3 N 4 /Ni 2 P catalyst is well characterized by X-Ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV–vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). The 2% MoS 2 –g-C 3 N 4 /Ni 2 P exhibited the best hydrogen generation rate of 298.1 μmol·g−1·h−1 under visible light illumination, which is 69 times more than that of pure g-C 3 N 4. Based on the evaluation of hydrogen generation rate and characteristic results, a possible mechanism is proposed, where 2D MoS 2 –g-C 3 N 4 p-n heterojunction could efficiently promote the electron-hole pair separation and Ni 2 P could significantly accelerate the hydrogen reduction step. The mechanism is supported by the results of PL and electrochemical analyses. [ABSTRACT FROM AUTHOR]

• N-doped porous carbons have been prepared by foam polystyrene. • The as-prepared composite exhibited excellent rate capability and cycle stability. • The cycle performance was up to 600 mAh g−1 at 1 A g−1 after 200 cycles. N-doped porous carbons (NPCs) prepared via carbonization of foam polymer materials and urea are promising anode materials of lithium-ion batteries (LIBs) for their low cost and high performance. Herein, polystyrene was mixed with Melanic Mc (5 wt%) and Azobisformamide (3 wt%) to prepared the precursors of porous carbon. NPCs with different N-doping levels were then obtained by the calcination of porous carbon/urea mixture with varied weight ratios. XPS and Raman characterizations illustrate that N-doping imposes negligible effects on the chemical states of N or C, but rather promotes the formation of disordered carbon and structural defects. BET measurement confirms that N-doping enlarges the surface area. The optimized NPCs with porous carbon/urea weight ratio of 1:5 exhibits high surface area of 508.3 m2·g−1 and the pore size is found to be around 3.66 nm. The capacities of NPCs achieve 600 mAh g−1 and 443 mAh g−1 over 200 cycles at 1 A g−1 and 5 A g−1 respectively. The excellent performance of NPC is ascribed to the enhanced surface area, defects and pores, providing abundant tunnels for lithium ion diffusion. Meanwhile, N-doping improves the electrical conductivity, which also enhances the rate performance. The facile synthetic route of NPCs as well as their excellent lithium storage performance shows great potential for the application in advanced lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Fe 3 O 4 encapsulated in porous carbon nanobowl (4Fe 3 O 4 @PCN-800) electrocatalyst for ORR and aqueous and solid-state Zn-air batteries has been successfully synthesized by a facile and scalable soft-template approach, which exhibits much better electrochemical activity than Pt/C. Furthermore, the solid-state Zn-air batteries exhibit encouraging flexibility, showing great potential in the application of flexible and wearable power sources. • Efficient nanobowl electrocatalysts are synthesized by a facile, scalable method. • 4Fe 3 O 4 @PCN-800 shows superior electrochemical activity for ORR than Pt/C. • Both liquid and solid-state Zn-air batteries are achieved with high performance. • It holds great potential in the application of flexible and wearable devices. Zn-air batteries have received extensive attention because of their high energy density, environmental friendliness, low cost and safety. It is vital to develop cost-effective and stable electrocatalysts for oxygen reduction reaction for Zn-air batteries. Herein, Fe 3 O 4 encapsulated in porous carbon nanobowls (Fe 3 O 4 @PCN) for oxygen reduction reaction are prepared by simple soft-template approach and calcination subsequently. The optimized catalyst 4Fe 3 O 4 @PCN-800 with uniformly doped Fe 3 O 4 nanoparticles and large surface area exhibits excellent catalytic performance and long-term durability. It displays 66 mV higher half-wave potential (0.911 V) than that of 20 wt% Pt/C catalysts in 0.1 M KOH electrolyte. It also shows excellent durability, only 5 mV attenuation of halfwave potential after 10,000 potential cycles. In addition, 4Fe 3 O 4 @PCN-800 possesses better methanol resistance than Pt/C, negligible current density fluctuation in the basic electrolyte with 3 M methanol. Impressively, when being employed as a cathode catalyst in both aqueous and solid-state Zn-air batteries, 4Fe 3 O 4 @PCN-800 presents higher open-circuit voltage, higher capacity and peak power density, and more stable discharge voltage plateaus than those of Pt/C. Furthermore, the solid-state Zn-air batteries with the optimal synthesized catalyst exhibit encouraging flexibility, which have enormous potential in the application of flexible and wearable power sources. [ABSTRACT FROM AUTHOR]

High performance flexible asymmetric supercapacitors based on carbon cloth are continuously prepared by a quick, low-cost, simple and scalable one-step electrochemical process within minutes without any other additives. The Fe 2 O 3 is electrochemically deposition carbon cloth for the negative electrode, while the PEDOT and MnO 2 are electrochemically co-deposited on carbon cloth for positive electrode. All processes take place within 1 min, therefore, this method can be applied in a continuous preparation mode for large-scale production, which implies its application potential in the industry. This is the first report of one-step continuous prepare of the flexible electrodes for supercapacitor. In addition, as assembled supercapacitors consisting of Fe 2 O 3 @carbon cloth and MnO 2 -PEDOT@carbon cloth, it achieves a high operating voltage of 2 V and a high energy density of 340 μW h cm−3 at a power density of 1.212 × 105 μW cm−3. This supercapacitor also possesses excellent flexibility and stability with 95% capacitance retained even after 1000 times bending. The larger-sized supercapacitor is further tested as watchband to power an electronic watch or light 41 LEDs for minutes. The low-cost continuous preparation method with high performance endows the flexible carbon cloth various promising applications, such as flexible asymmetric supercapacitors, flexible battery, catalysts and surface treatment. • One-step process within 1 min. • Fast, low-cost and scalable electrochemical preparation for supercapacitor. • Large-size flexible supercapacitor with high power density and energy density. [ABSTRACT FROM AUTHOR]

We report a highly promising electrolyte based on N-allyl-N-methylpiperidinium bis(trifluoromethanesulfonyl) imide (PP 13 *TFSI) and lithium difluoro(oxalato)borate (LiDFOB) to greatly improve the cycle performance of a Li/Li 1.1 Ni 0.25 Mn 0.65 O 2 battery at 2.5 V–4.6 V and 55 °C, which shows an initial discharge capacity of 181.7 mAh g−1 and a capacity retention of 90.9% after 150 cycles. A multiphase bilayer membrane structure is observed, which inhibits the decomposition of carbonate components and structure destruction. Physical characterization demonstrates the chemical interaction between PP 13 *+ and DFOB−, which prevents the cathode particle from structure degradation at 55 °C under high voltage. • The cycling performance of Li 1.1 Ni 0.25 Mn 0.65 O 2 is greatly promoted at 55 °C. • Bilayer film with high thermal stability formed by PP 13 *TFSI and LiDFOB. • The bilayer SEI film is essential to suppress the structure degradation of cathode. [ABSTRACT FROM AUTHOR]

Replacing Pt-based catalysts to alleviate energy and environmental crises for oxygen reduction reaction in fuel cells has become increasingly urgent. Herein, Fe and Co dual active sites and leaf-like 2D nanosheets are prepared by a low-cost and facile approach derived from a leaf-like zeolitic imidazolate framework (ZIF-L) precursor. The non-precious dual metal leaf-like 2D electrocatalyst exhibits better positive onset (0.98 V vs. RHE) and half-wave potential (0.831 V vs. RHE) compared with commercial Pt/C in alkaline media. This excellent performance is attributed to the structural characteristics of the leaf-like 2D nanosheet, including the large surface area and the synergistic effect of the Co and FeCo alloy and the nitrogen-doped carbon. The large surface area provides a large number of accessible active sites, and the dual metal and nitrogen-doped carbon enhance the mass transfer kinetics. Above all, the unique leaf-like 2D structure improves the activity and durability of oxygen reduction reaction. It is worth that the Zn-air battery we have made as air cathode demonstrates the excellent power density, specific capacity and stability. Impressively, the flexible battery has the outstanding performance. Image 1 • We developed a facile, low-cost and scalable approach to preparing 2D ORR catalyst. • Open up a green and efficient strategy to design a highly active catalyst. • 2D ORR catalyst delivered outstanding performance for the flexible Zn-air battery. [ABSTRACT FROM AUTHOR]

With the rapid development of new energy and the upgrading of electronic devices, structurally stable phase change materials (PCMs) have attracted widespread attentions from both academia and industries. Traditional cross-linking, composites, or microencapsulation methods for preparation of form stable PCMs usually sacrifice part of the phase change enthalpy and recyclability. Based on the basic polymer viscoelasticity and crystallization theories, here, a kind of novel recyclable polymeric PCM is developed by simple solution mixing ultrahigh molecular weight of polyethylene oxide (UHMWPEO) with its chemical identical oligomer polyethylene glycol (PEG). Rheological and leakage-proof experiments confirm that, even containing 90% of phase change fraction PEG oligomers, long-term of structure stability of PCMs can be achieved when the molecular weight of UHMWPEO is higher than 7000 kg mol -1 due to their ultralong terminal relaxation time and large number of entanglements per chain. Furthermore, because of the reduced overall entanglement concentration, phase change enthalpy of PCMs can be greatly promoted, even reaching to ≈185 J g -1 , which is larger than any PEG-based form stable PCMs in literatures. This work provides a new strategy and mechanism for designing physical-entanglements-supported form stable PCMs with ultrahigh phase change enthalpies., (© 2024 Wiley‐VCH GmbH.)

Achieving light modulation in the spectral range of 200-280 nm is a prerequisite for solar-blind ultraviolet communication, where current technologies are mainly based on the electro-luminescent self-modulation of the ultraviolet source. External light modulation through the electro-birefringence control of liquid crystal (LC) devices has shown success in the visible-to-infrared regions. However, the poor stability of conventional LCs against ultraviolet irradiation and their weak electro-optical response make it challenging to modulate ultraviolet light. Here, an external ultraviolet light modulator is demonstrated using two-dimensional boron nitride LC. It exhibits robust ultraviolet stability and a record-high specific electro-optical Kerr coefficient of 5.1 × 10⁻ 2 m V -2 , being three orders of magnitude higher than those of other known electro-optical media that are transparent (or potentially transparent) in the ultraviolent spectral range. The sensitive response enables fabricating transmissive and stable ultraviolet-C electro-optical Kerr modulators for solar-blind ultraviolet light. An M-ary coding array with high transmission density is also demonstrated for solar-blind ultraviolet communication., (© 2024 Wiley‐VCH GmbH.)

Solid-state lithium-metal batteries constructed by in-situ solidification of cyclic ether are considered to be a critical strategy for the next generation of solid-state batteries with high energy density and safety. However, the poor thermal/electrochemical stability of linear polyethers and severe interfacial reactions limit its further development. Herein, in-situ ring-opening hybrid crosslinked polymerization is proposed for organic/inorganic hybrid polymer electrolyte (HCPE) with superior ionic conductivity of 2.22 × 10 -3 S cm -1 at 30 °C, ultrahigh Li + transference number of 0.88, and wide electrochemical stability window of 5.2 V. These allow highly stable lithium stripping/plating cycling for over 1000 h at 1 mA cm -2 , which also reveal a well-defined interfacial stabilization mechanism. Thus, HCPE endows assembled solid-state lithium-metal batteries with excellent long-cycle performance over 600 cycles at 2 C (25 °C) and superior capacity retention of 92.1%. More importantly, the proposed noncombustible HCPE opens up a new frontier to promote the practical application of high safety and high energy density solid-state batteries via in-situ solidification., (© 2023 Wiley-VCH GmbH.)

Ultrahigh molecular weight polyethylene (UHMWPE) is a semicrystalline polymer renowned for its exceptional mechanical properties, making it a popular material in various high-tech fields. Its mechanical attributes are predominantly governed by its crystalline structures, which may experience alterations in the chain conformation and interchain packing during mechanical deformation. This phenomenon leads to the emergence of distinct polymorphs with unique lattice structures. The investigation of stress-stabilized crystal structures of UHMWPE under tensile stress currently poses challenges with certain aspects remaining unclear. To address this, in this study, time-resolved X-ray wide-angle scattering (TR-WAXS) experiments of biaxially stretched UHMWPE films under in situ tensile conditions were conducted. Experimental results revealed two distinct stress-stabilized crystal phases of UHMWPE that differed from those previously reported. These stress-stabilized phases have been identified as the stress-stabilized orthorhombic crystal phase and the stress-stabilized monoclinic crystal phase, and their corresponding lattice parameters have been accurately calculated through an ab initio computational method. These findings provide deeper insights into UHMWPE's behavior under mechanical strain, opening other avenues for further academic exploration and potential applications in cutting-edge fields.

Smart windows nowadays undertake the esteemed obligation of reducing energy consumption as well as upgrading living experience. This project aims to devise a smart window that responds to both electricity and heat, with the intention of achieving energy efficiency, privacy preservation, and enhanced decorative attributes. Through the implementation of a novel electrochromic material design, coupled with the optimization of electrochromic devices (ECDs), a high-performance ECD is obtained, demonstrating coloring/bleaching time of 0.53/0.16 s, a transmittance modulation of 78% (from 99% to 21%), and superior performance in six dimensions. Furthermore, temperature-responsive units and an ionic liquid are incorporated into the electrolyte system to create a novel thermochromic gel electrolyte with transmittance modulation from 80% to 0%, and excellent thermal insulation (6.4 °C reduction). Ultimately, an electro- and thermochromic device is developed, featuring an ultrafast color-switching speed of 0.82/0.60 s and multiple working modes. Overall, this work showcases a prospective design pathway for the development of next-generation ultrafast-switching, and energy-efficient intelligent windows., (© 2023 Wiley-VCH GmbH.)

Strong and tough hydrogels are promising candidates for flexible electronics, biomedical devices, and so on. However, the conflict between improving the mechanical strength and toughness properties of polysaccharide-based hydrogels remains unsolved. Herein, a strategy is proposed to produce a hierarchically structured cellulose hydrogel that combines solution annealing and dual cross-linking treatment approaches. The solution annealing considerably increases the hydrophobic stacking and chemical cross-linking of the cellulose chains, thereby facilitating their subsequent self-assembly and recrystallization during the chemical and physical cross-linking processes. The cellulose hydrogels exhibit superposed chemically and physically cross-linked domains comprising homogeneous nanoporous network structures, which in turn are composed of interconnected cellulose nanofibers and cellulose II crystallite hydrates. These cellulose hydrogels exhibit a high water content of 76-84% and excellent mechanical properties that compare favorably to those of biomacromolecule-based hydrogels. The prepared hydrogels exhibit a mechanical strength and work of fracture of 21 ± 3 MPa and 2.6 ± 0.4 MJ m -3 under compression, and 7.2 ± 0.7 MPa and 5.9 ± 0.6 MJ m -3 under tension, respectively. It is anticipated that this strategy will be applicable to other biomacromolecules and crystalline polymers, and that it will enable the construction of other hydrogels exhibiting high mechanical performances., (© 2023 Wiley-VCH GmbH.)

FeNC catalysts demonstrate remarkable activity and stability for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells and Zn-air batteries (ZABs). The local coordination of Fe single atoms in FeNC catalysts strongly impacts ORR activity. Herein, FeNC catalysts containing Fe single atoms sites with FeN 3 , FeN 4 , and FeN 5 coordinations are synthesized by carbonization of Fe-rich polypyrrole precursors. The FeN 5 sites possess a higher Fe oxidation state (+2.62) than the FeN 3 (+2.23) and FeN 4 (+2.47) sites, and higher ORR activity. Density functional theory calculations verify that the FeN 5 coordination optimizes the adsorption and desorption of ORR intermediates, dramatically lowering the energy barrier for OH - desorption in the rate-limiting ORR step. A primary ZAB constructed using the FeNC catalyst with FeN 5 sites demonstrates state-of-the-art performance (an open circuit potential of 1.629 V, power density of 159 mW cm -2 ). Results confirm an intimate structure-activity relationship between Fe coordination, Fe oxidation state, and ORR activity in FeNC catalysts., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)

Heat-resistant supercapacitors with excellent mechanical strength are highly required for flexible and wearable electronics in our daily life. Here, high-performance and heat-resistant solid-state supercapacitors based on poly( para -phenylene terephthalamide) fibers/Ag/poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT:PSS)&carbon nanotubes (PPTA/Ag/PCNTs) have been fabricated for the first time. Due to the toughness of the PPTA fibers and the excellent electroconductivity of the composite fiber, the PPTA/Ag/PCNTs-based supercapacitor exhibits good electrochemical performance together with brilliant mechanical strength and bending durability. Moreover, the heat resistance of tough PPTA/Ag/PCNTs fiber and ionic liquid gel electrolyte endow the supercapacitor with stability at temperatures as high as 80 °C and the capacitance can return to more than 80% after the heat treatment. The power density or energy density of the supercapacitor assembled on PPTA/Ag/PCNTs fiber electrodes is higher than that of any other polymer fiber-related supercapacitor. This work adds to the study of high-performance supercapacitors based on polymer fibers and provides the possibility to apply PPTA fiber for energy storage devices with flexibility and heat resistance.

Constructing a 0D/3D p-n heterojunction is a feasible strategy for accelerating photo-induced charge separation and promoting photocatalytic H 2 production. In this study, a 0D/3D MoS 2 /g-C 3 N 4 (0D/3D-MCN) photocatalyst with a p-n heterojunction was prepared via a facile light-assisted deposition procedure, and the 3D spongy-like g-C 3 N 4 (3D-CN) was synthesized through simple thermolysis of NH 4 Cl and melamine mixture. For comparison, 2D-MoS 2 nanosheets were also embedded in 3D-CN by a solution impregnation method to synthesize a 2D/3D-MCN photocatalyst. As a result, the as-prepared 0D/3D-MCN-3.5% composite containing 3.5 wt% 0D-MoS 2 QDs exhibited the highest photocatalytic H 2 evolution rate of 817.1 μmol h -1 g -1 , which was 1.9 and 19.4 times higher than that of 2D/3D-MCN-5% (containing 5 wt% 2D-MoS 2 nanosheets) and 3D-CN, respectively. The results of XPS and electrochemical tests confirmed that a p-n heterojunction was formed in the 0D/3D-MCN-3.5% composite, which could accelerate the electron and hole movement in the opposite direction and retard their recombination; however, it was not found in 2D/3D-MCN-5%. This study revealed the relationship among the morphologies of MoS 2 using g-C 3 N 4 as a substrate, the formation of a p-n heterojunction, and the H 2 evolution activity; and provided further insights into fabricating a 3D g-C 3 N 4 -based photocatalyst with a p-n heterojunction for photocatalytic H 2 evolution., Competing Interests: There are no any financial conflicts to declare., (This journal is © The Royal Society of Chemistry.)

KTaO 3 /Au hetero-nanostructures were synthesized by in-situ reduction of HAuCl 4 on the surface of hydrothermally-grown KTaO 3 sub-micron cubes. The concentration of Au source was found to be a critical factor in controlling the hetero-nucleation of Au nanoparticles on the surface of KTaO 3 sub-micron cubes. Loading of Au particles on KTaO 3 nanocrystals enriched KTaO 3 additional UV-vis absorption in the visible light region. Both KTaO 3 and KTaO 3 /Au nanocrystals were shown to be active in the photo-degradation of p-nitrophenol, while the loading of Au on KTaO 3 clearly improved the photo-degradation efficiency of p-nitrophenol compared to that on bare KTaO 3 nanocrystals, probably due to the improved light absorption and charge separation.

Sodium-ion batteries (SIBs) have attracted tremendous interest and become a worldwide research hotpot owing to their low cost and abundant resources. To obtain suitable anode materials with excellent performance for SIBs, an effective and controllable strategy is presented to fabricate SnS 2 nanosheets coating on nanohollow cubic CoS 2 /C (CoS 2 /C@SnS 2 ) composites with a hollow structure using Co-metal-organic frameworks as the starting material. As anodes for SIBs, the CoS 2 /C@SnS 2 electrode exhibits ultralong cycle life and excellent rate performance, which can maintain a high specific capacity of 400.1 mAh g -1 even after 3500 cycles at a current density of 10 A g -1 . When used in a full-cell, it also shows enhanced sodium storage properties and delivers a high reversible capacity of 567.3 mAh g -1 after 1000 cycles at 1 A g -1 . This strategy can pave a way for preparing various metal sulfides with fascinating structure and excellent performance for the potential application in energy storage area., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)