Search Results (1,119)

The demand for high-energy-density and fast-charging solid-state lithium metal batteries (SSLMBs) often subjects practical devices to internal thermal loads, making high-temperature operation a common operational condition rather than an isolated scenario. To address the interfacial degradation and dendrite growth accelerated by such thermomechanical stresses, we developed a composite gel electrolyte (CGE) by incorporating an optimal concentration of active Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) into a fluoropolymer network. The abundant Lewis acidic sites on the LLZTO surfaces promote competitive solvation decoupling by interacting with anions, thereby modulating the primary solvation sheath of Li⁺. This localized modulation lowers the lithium-ion migration activation energy to 0.248 eV and facilitates a dual-interfacial passivation mechanism. Specifically, a rigid, inorganic-rich solid electrolyte interphase (SEI) forms to suppress morphological instability at the lithium anode, while an organic-dominated cathode electrolyte interphase (CEI) enhances the oxidative stability up to 4.3 V. As a result, symmetric cells demonstrate stable electrodeposition for over 450 h at 80 °C and 0.5 mA cm⁻². Furthermore, NCM811/Li full cells utilizing this CGEs exhibit significantly improved thermal resilience and cycling stability. Full article

To overcome active site blockage and poor interfacial contact in traditional syntheses, PtNi bimetallic nanoparticles were grown in situ on a microporous carbon paper via pulse electrodeposition. Firstly, the impact of deposition potential was investigated. The results indicate that the deposition potential significantly modulates the surface Pt⁰/Pt²⁺ ratio; concurrently, a shift toward more negative potentials intensified nanoparticle agglomeration. The effects of the duty cycle were investigated at an optimal deposition potential of −0.95 to −0.4 V. A duty cycle of 30% yielded the optimal Pt⁰/Pt²⁺ ratio. Furthermore, TEM revealed a coexisting strain profile of bulk PtNi lattice contraction and localized expansion at peripheral Pt (111) facets. This synergistic tuning of surface valence and strain optimizes the thermodynamic balance between oxygen adsorption and intermediate desorption on Pt sites. In summary, the optimal catalyst, prepared at a deposition potential of −0.95 V and a duty cycle of 30%, showed the best reaction behavior in the oxygen reduction reaction with an initial onset potential of 0.92 V (vs. RHE). After 5000 cycles of testing, the catalyst showed a constant durability, with the onset potential degrading only marginally to 0.87 V. This work successfully demonstrates that the surface morphology and valence states of the catalyst can be effectively tailored by regulating the pulse voltage and duty cycle. Full article

To investigate the deterioration law of the mechanical properties of PVA-fiber-reinforced rubber concrete under the combined action of high-temperature and salt erosion, physical index tests, dynamic mechanical property experiments, and microstructural morphology observations were carried out on specimens subjected to different temperatures (ambient temperature, 100 °C, 300 °C) and various solution attacks (water, 5% NaCl, 5% Na₂SO₄, and 5% NaCl + 5% Na₂SO₄ mixture). The results show that, after exposure to 300 °C, the PVA fibers melt and the rubber pyrolyzes, since this temperature exceeds their melting points. A residual pore network is formed inside the matrix, and the damage degree of ultrasonic pulse velocity is about 2.3 times that of the 100 °C group. Although salt solution and its crystallization products can physically fill the pores and cause a partial recovery of pulse velocity, this change is mainly due to the alteration of the pore medium and does not represent a substantial restoration of the microstructure. The effects of different salt solutions on dynamic mechanical properties vary significantly: Sulfate erosion improves the dynamic performance significantly at ambient temperature by forming gypsum and ettringite to fill pores, but this strengthening effect disappears after 300 °C. Sodium chloride attack generates Friedel’s salt and consumes C₃A, leading to general strength deterioration. In composite salt erosion, the competitive and synergistic effects of Cl⁻ and SO₄²⁻ destabilize erosion products and weaken interfacial bonding, resulting in consistent decreases in dynamic compressive strength and elastic modulus under all temperatures and impact pressures. The strength reduction reaches 66.2% after 300 °C. Microscopic analysis confirms that composite salt erosion leads to the dissolution of ettringite and loose structure, which verifies the synergistic deterioration law of macroscopic properties. This study systematically reveals the damage evolution mechanism of PVA-fiber-reinforced rubber concrete under the coupled action of high-temperature and salt erosion, and provides a theoretical basis for the dynamic bearing capacity evaluation and durability design of concrete structures in such coupled environments. Full article

The photoelectrochemical splitting (PEC) of water provides a direct route to converting solar energy into storable chemical fuels. When illuminated, a semiconductor photoelectrode can absorb light and generate electron-hole pairs, which participate in interfacial redox reactions at the semiconductor-electrolyte junction. Therefore, to achieve high-performance PEC, photoelectrodes with optimized optical absorption and charge have been explored. This review analyzes recent fabrication strategies used to design photoelectrodes for the PEC dissociation of water. Physical fabrication techniques, including pulsed laser deposition, magnetron sputtering, and physical vapor deposition, allow for precise control of film thickness, crystallinity, and defect density, critical parameters for efficient charge transport. Typically, in physical methods, reported photocurrent densities span from ~10⁻² to 10¹ mAcm⁻², depending on the semiconductor material, nanostructure design, and interfacial engineering strategies. Chemical synthesis methods, such as hydrothermal growth, successive ion layer adsorption and reaction, and microemulsion techniques, provide greater compositional flexibility and enable controlled doping, surface functionalization, and the formation of nanostructured morphologies. Finally, hybrid fabrication strategies integrate physical and chemical processes within a single synthesis framework to combine structural precision with compositional tuning capabilities. These approaches enable the development of advanced architecture such as heterojunctions, core–shell nanostructures, and catalyst-modified interfaces, which enhance light absorption and optimize interfacial transfer. Furthermore, theoretical and computational tools are here analyzed as complementary approaches that guide the rational design and optimization of photoelectrochemical materials and devices. Full article

Fe₂O₃-reinforced PMMA nanocomposites were prepared by melt blending using a twin-screw micro-extruder. Fixed Fe₂O₃ loading of 2.5 wt.% was employed, and mixing times of 6 and 12 min were used to obtain nanocomposites with different dispersion characteristics. The structural and morphological properties of the samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), while their thermal degradation behavior was evaluated by differential thermal and thermogravimetric analyses (DTA/TG). The activation energies of thermal degradation were calculated using the Kissinger, Takhor, and Augis–Bennett methods. Increasing the mixing time improved nanoparticle dispersion and reduced agglomeration. The addition of Fe₂O₃ slightly decreased the characteristic degradation temperatures of PMMA, while the activation energy increased for the better-dispersed sample. The results indicate that interfacial interactions and particle dispersion play important roles in the thermal degradation behavior of PMMA/Fe₂O₃ nanocomposites. Full article

Developing sustainable electrode materials from renewable biomass is important for improving the environmental sustainability of lithium-ion batteries (LIBs). Sugarcane bagasse lignin, an abundant agricultural byproduct, is a promising precursor for lignin-derived carbon anode materials, yet systematic comparative studies on catalyst-dependent structure evolution and LIB performance remain limited. In this study, lignin extracted from sugarcane bagasse by an ethanosolv process was converted into Fe- and Ni-catalyzed lignin-derived carbon materials via catalytic pyrolysis at 900 °C. The effects of catalyst type, metal-to-lignin ratio, and pyrolysis holding time on textural properties, structural features, and electrochemical behavior were systematically investigated. Among the studied conditions, the Fe-catalyzed sample prepared at a metal-to-lignin ratio of 1:2.5 and a holding time of 3 h (GLKL-2.5Fe-3h) exhibited the highest BET surface area (332.71 m² g⁻¹) and the most developed porous morphology. SEM, TEM, Raman, and XRD analyses indicated catalyst-dependent differences in pore development, carbon domain morphology, and local graphitic ordering, with Fe- and Ni-catalyzed samples following distinct structural evolution pathways. Electrochemical testing showed that GLKL-2.5Fe-3h delivered the highest initial discharge capacity (759 mAh g⁻¹), retained 165 mAh g⁻¹ after 500 cycles, and exhibited more favorable rate performance and lower apparent interfacial resistance than the other tested samples under the same conditions. In contrast, the Ni-catalyzed and solvothermally treated samples showed lower capacity retention and/or less favorable electrochemical behavior. These results demonstrate the strong effect of catalyst type on the structure-performance relationship of bagasse lignin-derived carbon anodes and support Fe-catalyzed lignin-derived carbon as a promising sustainable anode candidate for LIB applications. Full article

To mitigate the interlayer defects and weak interfacial adhesion inherent in FFF-printed parts, thereby facilitating subsequent supercritical foaming applications, a microwave-assisted interlayer healing strategy is developed for FFF-printed, supercritical CO₂-foamed thermoplastic polyurethane (TPU) by incorporating aminated helical multi-walled carbon nanotubes (AS-MWCNTs). Owing to their unique helical morphology, AS-MWCNTs exhibit enhanced microwave absorption and localized heating capability, enabling selective thermal activation at interlayer regions within the foamed architecture. Microwave irradiation induces localized softening of the TPU matrix and promotes polymer chain mobility and interdiffusion across layer interfaces, while preserving the cellular morphology and bulk foamed structure. By optimizing AS-MWCNT loading, substantial improvements in interlayer bonding strength, energy absorption, and overall mechanical performance are achieved. This work provides an effective strategy to restore interlayer integrity in supercritical CO₂-foamed, additive manufactured elastomers and offers insights into the design of microwave-responsive, self-healing cellular materials. Full article

The inherent hydrophobicity of polyolefin separators significantly impedes rapid electrolyte wetting, thereby limiting the electrochemical performance of lithium-ion batteries. Cellulose, as a hydroxyl-rich natural polymer, serves as an ideal material for enhancing the interface properties of separators. However, there is still a lack of systematic understanding regarding how the morphological structures of cellulose (such as granular, fibrous, or network-like forms) influence the coating structure and ion transport mechanisms. Here, three representative cellulose derivatives—microcrystalline cellulose (MCC), cellulose nanofibers (CNF), and bacterial cellulose (BC)—were selected to construct functionalized polypropylene (PP) composite separators through vacuum filtration. Experimental results demonstrate that all three cellulose coatings reduced contact angles from 50.8° to below 10°, significantly enhancing interfacial affinity. Systematic comparison reveals that cellulose configuration decisively influences separator performance: unlike the dense fiber entanglement networks formed by CNF and BC, the unique rigid granular packing structure of MCC maintains hydrophilicity while establishing more permeable ion transport pathways. Among these, MCC@PP exhibited optimal electrochemical performance, with the lithium-ion migration number increasing to 0.41 and a capacity retention rate of 88.04% after 100 cycles at 0.5 A/g. This study elucidates the relationship between cellulose configuration and the modification of separator performance, demonstrating that MCC represents a more efficient, robust, and cost-effective option for separator modification compared to complex fiber networks. Full article

To investigate the sulfate corrosion resistance of cast-in-place repair concrete incorporating recycled coarse aggregate (RCA) under partially exposed conditions, cast-in-place repair concrete specimens with different RCA contents (0%, 30%, and 50%) were immersed in Na₂SO₄ solution. The study systematically investigated the changes in apparent morphology, dimensions, mass, and mechanical properties of the specimens under sulfate corrosion. SEM, XRD, TG/DTG, and MIP were used to characterize the microstructure and mineral composition of the specimens at different corrosion ages. Results indicate that RCA cast-in-place repair concrete partially exposed to a sulfate corrosion environment undergoes coupled physical and chemical corrosion, and the interfacial zone between the recycled aggregate concrete to the base concrete represents the most vulnerable region in the composite system. Incorporating 30% RCA can effectively reduce the degradation rate of specimens under sulfate corrosion, enhance the compactness of the bonding interface, and optimize the interfacial bond strength, compressive strength, and pore structure of the specimens. Excessive RCA content disrupts the internal pore structure, accelerates sulfate ion ingress, and weakens the interfacial bond strength. The presence of RCA significantly reduces the interfacial shear strength of the specimens. After 360 days of sulfate corrosion, specimens featuring 30% and 50% RCA contents exhibit a reduction in shear strength of 15.91% and 40.0%, respectively, compared with the 0% RCA content specimen. Research findings provide a theoretical basis for the application of RCA in concrete repair engineering. Full article

Anode-less battery architectures, which eliminate the host anode material, have attracted considerable attention as a promising approach to increase energy density, simplify cell manufacturing, and improve safety in next-generation energy storage systems. This review provides a structured and integrative overview on the current research landscape of anode-less cells, spanning both liquid- and solid-electrolyte technologies. It first introduces the fundamental principles, key advantages, and inherent challenges of the anode-less concept. Advanced characterization techniques, including electrochemical, interfacial, morphological, and operando approaches, are then discussed as essential tools for probing metal plating/stripping behavior and degradation mechanisms. The core of the review examines how system design governs performance, addressing strategies for liquid electrolytes, including current collector design, electrolyte formulation, and deposition control, as well as solid electrolytes, with an emphasis on interfacial engineering, fundamental limitations, and extensions to Na- and K-based batteries. By integrating insights across these systems, the review identifies critical challenges, including unstable solid-electrolyte interphases, dendrite formation, and interfacial contact loss. Finally, a development pyramid is introduced as a conceptual framework linking fundamental research to practical implementation, outlining key priorities from interface control and full-cell compatibility to long-term reliability while also highlighting industrial pathways toward hybrid and fully solid-state anode-less batteries. Full article

Glycolysate and glycerolysate—organic substances recovered from the chemical recycling of polyurethane waste—were investigated as sustainable plasticizers for acrylonitrile-butadiene rubber composites filled with 30 phr of calcium lignosulfonate or kraft lignin. The study evaluated the impact of these recycled plasticizers (added at 10 and 15 phr) on the curing process, morphology, rheology, mechanical and dynamic mechanical performances. Rheological analysis confirmed that both plasticizers significantly reduced the complex viscosity of the rubber compounds, with the effect being most pronounced at the 15 phr loading. While the incorporation of glycolysate and glycerolysate slightly extended the optimum cure time and decelerated the curing process, the cross-link density remained consistently within the range of 3.5–4 × 10⁻⁴ mol·cm⁻³. Morphological studies revealed that the plasticizers facilitated better dispersion of both lignin types and improved interfacial adhesion. However, the mechanical response differed significantly depending on the filler type. A consistent increase in elongation at break was observed only for composites filled with kraft lignin, where values rose from 341% for the reference up to 571% for the sample with 15 phr of glycolysate. In contrast, the application of plasticizers to calcium lignosulfonate-filled composites led to an initial decrease in both tensile strength and elongation at break. Notably, kraft lignin-filled composites exhibited superior overall mechanical performance, with glycolysate effectively maintaining tensile strength levels comparable to the reference. While both recovered substances performed effectively as processing aids, they had a negligible effect on the glass transition temperature. The results demonstrated that these recovered polyurethane derivatives are highly effective, sustainable alternatives to conventional plasticizers, showing a clear synergistic effect particularly with kraft lignin. Full article

Hollow graphitic nanoshells (HGSs) are widely investigated as battery materials because their conductive shells and internal voids can simultaneously influence ion transport, electron percolation, and mechanical stress accommodation. Yet, the field remains largely morphology-driven, with performance often attributed generically to “hollowness” rather than to structural parameters. This review examines HGSs from a parameter-oriented perspective. It highlights key structural features, including graphitization degree, shell thickness, cavity size, pore architecture, and defect or dopant chemistry. These features collectively shape electrochemical behavior. We discuss how these features influence transport kinetics, interphase stability, volumetric efficiency, and mechanical resilience across insertion, metal anode, multivalent, solid-state, and halogen chemistries. Major synthesis approaches, including hard-templated, soft-templated, self-templated, and biomass-derived routes, are evaluated based on the structural control they provide and the influence of synthesis conditions on shell architecture, graphitic ordering, and pore structure. Special attention is given to how these structural features develop during processing and how they affect ion accessibility, conductivity, and stability. Finally, we outline a shift toward quantitative, parameter-driven engineering supported by operando diagnostics, electrode-level modeling, and standardized reporting. HGSs will only achieve practical relevance when structural optimization extends beyond particle morphology to transport uniformity, interfacial stability, network connectivity, and life-cycle responsibility. Full article

This study presents the successful electrodeposition of polyaniline (PANI) and TiO₂/PANI composites on boron-doped diamond (BDD) and fluorine-doped tin oxide (FTO) substrates via cyclic voltammetry. Using 20 scan cycles in 0.5 M H₂SO₄, we synthesized thin films with tailored electrochemical properties. The formation of PANI was confirmed by characteristic redox peaks in the voltammograms, while FTIR spectroscopy identified key functional groups and bonding interactions between TiO₂ and PANI. Morphological analysis via optical and scanning electron microscopy revealed uniform but cracked surfaces influenced by TiO₂ loading. Composite electrodes with molar ratios of 2:1, 4:1, and 6:1 (TiO₂:PANI) were compared, showing increased titanium content with higher ratios, as confirmed by EDS. This work offers a reproducible route for designing modified electrodes with enhanced interfacial properties. Full article

This work focused on the investigation of sulfonated lignin as a novel and sustainable reinforcing filler for polyamide 6 (PA6) composites. Different formulations were thus prepared by melt compounding, varying the lignin content (5, 10, and 20 wt%). The interaction between lignin and PA6 was systematically studied through rheological, structural, morphological, thermo-mechanical, and flammability tests. Rheological measurements showed an increase in the complex viscosity and viscoelastic moduli with increasing lignin content, suggesting restricted polymer chain mobility and the formation of strong physical interactions between the molten PA6 and the lignin particles. Microstructural observations through FESEM highlighted a good dispersion of lignin particles and efficient filler–matrix interfacial adhesion. Moreover, the addition of lignin significantly increased the tensile stiffness of the composites (up to 3.4 GPa), and a lignin content of 10 wt% enhanced the tensile strength up to 58.4 MPa (i.e., +45% compared to neat PA6) without compromising the ductility. Finally, UL-94 tests revealed an improvement in flame retardancy at higher lignin contents due to the intrinsic char-forming ability of this filler. These results demonstrated that lignin could be an effective multifunctional bio-based filler that can improve the thermo-mechanical performance of PA6 without the need for compatibilizing agents. Full article

In this work, biodegradable poly(vinyl alcohol) (PVA) and ferroelectric poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) nanofibers were successfully fabricated via co-electrospinning. The morphology and microstructure of co-electrospun PVA/P(VDF-HFP) nanofibers were analyzed, demonstrating that P(VDF-HFP) incorporation significantly affected fiber diameter and phase distribution. These structural features altered the fiber diameter and surface area of the co-electrospun system, thereby affecting interfacial polarization and the resulting dielectric and energy storage performance. As a result, the dielectric constant of the PVA/P(VDF-HFP) nanofibers (M1) was enhanced by up to 1.8 times compared with pure PVA nanofibers (M0), owing to interfacial polarization arising from increased surface charge accumulation at the PVA/P(VDF-HFP) interfaces. Meanwhile, dielectric loss and electrical conductivity were effectively controlled, indicating improved electrical stability of the co-electrospun system. Furthermore, ferroelectric and energy storage analyses revealed that appropriate incorporation of P(VDF-HFP) and phase distribution significantly enhanced polarization and energy storage performance. The energy storage density increased from 0.83 to 3.21 mJ cm⁻³ at 20 MV m⁻¹, corresponding to an improvement of 287% while maintaining a high energy efficiency of approximately 90%. Owing to their favorable dielectric properties, mechanical flexibility, and environmental compatibility, the co-electrospun PVA/P(VDF-HFP) nanofibers demonstrate great potential for low-field wearable and biomedical energy storage devices. Full article