Search Results (418)

Inkjet printing enables contactless deposition onto fragile substrates for printed energy-storage devices and supports flexible batteries and supercapacitors with reduced material use. This review examines multilayer and interdigital architectures and analyzes how ink rheology, droplet formation, colloidal interactions, and the printability window govern performance. For batteries, reported inkjet-printed electrodes commonly deliver capacities of ~110–150 mAh g⁻¹ for oxide cathodes at C/2–1 C, with coulombic efficiency ≥98% and stability over 10²–10³ cycles; silicon anodes reach ~1.0–2.0 Ah g⁻¹ with efficiency approaching 99% under stepwise formation. Typical current densities are ~0.5–5 mA cm⁻² depending on areal loading, and multilayer designs with optimized drying and parameter tuning can yield rate and discharge behavior comparable to cast films. For supercapacitors, inkjet-printed microdevices report volumetric capacitances in the mid-hundreds of F cm⁻³, translating to ~9–34 mWh cm⁻³ and ~0.25–0.41 W cm⁻³, with 80–95% retention after 10,000 cycles and coulombic efficiency near 99%. In solid-state configurations, stability is enhanced, although often accompanied by reduced areal capacitance. Although solids loading is lower than in screen printing, precise material placement together with thermal or photonic sintering enables competitive capacity, rate capability, and cycle life while minimizing waste. The review consolidates practical guidance on ink formulation, printability, and defect control and outlines opportunities in greener chemistries, oxidation-resistant metallic systems, and scalable high-throughput printing. Full article

Potassium–selenium (K-Se) batteries have emerged as a promising energy storage system in view of their high theoretical energy density and low cost. However, their practical application is restricted due to challenges such as polyselenide shuttling, low redox activity, and significant cathode volume expansion during cycling, leading to inferior Coulombic efficiency and a short cycling lifespan. Carbon-based materials, with their superior electronic conductivity, adjustable pore structures, and robust chemical stability, have been extensively studied and employed as cathode materials in K-Se batteries, demonstrating remarkable potential in addressing the above-mentioned issues. Considering the rapidly growing research interest in this topic in recent years, herein, we comprehensively summarize recent advances in the application of carbon-based materials as cathodes in K-Se batteries. First, we introduce the properties, key challenges, and optimization strategies of K-Se batteries, including encapsulating Se within carbon materials, engineering chemisorptive hosts, and electrocatalyzing redox reactions. Furthermore, we discuss the relationship between fabrication strategies, micro/nanostructures, and electrochemical performances. Finally, we propose future prospects for the rational design and application of carbon-based cathodes in K-Se batteries and other alkaline metal–chalcogen batteries. Full article

The development of high-performance supercapacitor electrodes is crucial to meet the increasing demand for efficient and sustainable energy storage systems. Cobalt oxide (Co₃O₄), with its high theoretical capacitance, is a promising electrode material, but its practical application is hindered by poor conductivity limitations and structural instability during cycling. In this work, lanthanum La³⁺-doped Co₃O₄ nanocubes were synthesized via a hydrothermal approach to tailor their structural and electrochemical properties. Different doping concentrations (1, 3, and 5%) were introduced to investigate their influence systematically. X-ray diffraction confirmed the retention of the spinel phase with clear evidence of La³⁺ incorporation into the Co₃O₄ lattice. Also, Raman spectroscopy validated the structural integrity through characteristic Co-O vibrational modes. Scanning electron microscopy analysis revealed uniform cubic morphologies across all samples. The formation of the cubic spinel structure of 1% La³⁺-doped Co₃O₄ are confirmed from XPS and TEM studies. Electrochemical evaluation in a 3 M KOH electrolyte demonstrated that 1% La³⁺-doped Co₃O₄ nanocubes delivered the highest performance, achieving a specific capacitance of 1312 F g⁻¹ at 1 A g⁻¹ and maintaining a 79.8% capacitance retention and a 97.12% Coulombic efficiency over 10,000 cycles at 5 Ag⁻¹. It can be demonstrated that La³⁺ doping is an effective strategy to enhance the charge storage capability and cycling stability of Co₃O₄, offering valuable insights for the rational design of next-generation supercapacitor electrodes. Full article

MXenes, a rapidly emerging family of two-dimensional transition metal carbides and nitrides, have attracted considerable attention in recent years for their potential in next-generation energy storage technologies. In solid-state batteries (SSBs), they combine metallic-level conductivity (>10³ S cm⁻¹), adjustable surface terminations, and mechanical resilience, which makes them suitable for diverse functions within the cell architecture. Current studies have shown that MXene-based anodes can deliver reversible lithium storage with Coulombic efficiencies approaching ~98% over 500 cycles, while their use as conductive additives in cathodes significantly improves electron transport and rate capability. As interfacial layers or structural scaffolds, MXenes effectively buffer volume fluctuations and suppress lithium dendrite growth, contributing to extended cycle life. In solid polymer and composite electrolytes, MXene fillers have been reported to increase Li⁺ conductivity to the 10⁻³–10⁻² S cm⁻¹ range and enhance Li⁺ transference numbers (up to ~0.76), thereby improving both ionic transport and mechanical stability. Beyond established Ti-based systems, double transition metal MXenes (e.g., Mo₂TiC₂, Mo₂Ti₂C₃) and hybrid heterostructures offer expanded opportunities for tailoring interfacial chemistry and optimizing energy density. Despite these advances, large-scale deployment remains constrained by high synthesis costs (often exceeding USD 200–400 kg⁻¹ for Ti₃C₂T_x at lab scale), restacking effects, and stability concerns, highlighting the need for greener etching processes, robust quality control, and integration with existing gigafactory production lines. Addressing these challenges will be crucial for enabling MXene-based SSBs to transition from laboratory prototypes to commercially viable, safe, and high-performance energy storage systems. Beyond summarizing performance, this review elucidates the mechanistic roles of MXenes in SSBs—linking lithiophilicity, field homogenization, and interphase formation to dendrite suppression at Li|SSE interfaces, and termination-assisted salt dissociation, segmental-motion facilitation, and MWS polarization to enhanced electrolyte conductivity—thereby providing a clear design rationale for practical implementation. Full article

Based on the steel sheet pile cofferdam project for the main bridge piers of a cross-sea bridge, finite element numerical simulations were conducted to analyze the influence of construction sequences in marine environments, as well as the effects of initial water levels and support positions under various construction conditions on the stress and deformation behavior of steel sheet piles. Using a staged construction simulation with a Mohr–Coulomb soil model and stepwise activation of loads/excavation, this study delivers practically relevant trends: staged dewatering halves the sheet pile head displacement (top lateral movement <0.08 m vs. ~0.16 m in the original scheme) and mobilizes the support system earlier, while slightly increasing peak bending demand (~1800 kN·m) at the bracing elevation; the interaction between water head and brace elevation is explored through fitted response curves and summarized in figures/tables, and soil/structural properties are tabulated for reproducibility. The results indicate that a well-designed dewatering process, along with the coordination between water levels and internal support positions, plays a critical role in controlling deformation. The findings offer valuable references for the design and construction of sheet pile cofferdams in marine engineering under varying construction methods and water level conditions. Full article

In order to solve the problems of mass transfer polarization spatiotemporal distribution variations, uncontrollable regulation error, and accelerated capacity decay caused by ion crossover in high-power vanadium liquid flow batteries (VFBs), a three-dimensional battery model with a flow-type flow field based on the three-dimensional transient COMSOL Multiphysics^® 6.1 numerical modeling method was developed in this study. The model combines the ion transmembrane migration equation with the mass transfer polarization theory, constructs an objective function to quantify the regulation error, and is validated by multifluid-field structural simulations. The results indicate the following: (1) Ion crossover induces a 3–5% electrolyte concentration deviation and a current density distribution bias reaching 11%; (2) The intensity of mass transfer polarization exhibits a linear increase with the flow rate difference between the positive and negative electrodes; (3) Ion crossover significantly degrades system performance, causing Coulombic efficiency (CE) and Energy efficiency (EE) to decrease by 1.1% and 1.5%, respectively. This research demonstrates that unlike conventional flow field optimization, our strategy quantifies the regulation error by directly compensating for the ΔQ caused by ion crossing, and further regulation minimizes the effect, providing a theoretical basis for mass transfer intensification and capacity recovery in flow batteries. Full article

The cycling stability and widespread practical implementation of aqueous zinc ion batteries (AZIBs) are impeded by dendrite growth and the hydrogen evolution reaction (HER). Herein, theaflavins, a low-cost organic bio-compounds and a major component of tea, were innovatively introduced as an electrolyte additive for AZIBs to address these challenges. When added into the electrolyte, theaflavins, with their strong de-solvation capability, facilitated the more uniform and stable diffusion of zinc ions, effectively suppressing dendrite formation and HER. This, in turn, significantly enhanced the coulombic efficiency (>95% in Zn/Cu system) and the stability of the zinc deposition/stripping process in Zn/Zn system. The Zn/Zn symmetric battery system stably cycled for approximately 3000 h at current densities of 1 mA/cm². Compared with H₂O molecules, theaflavins exhibited a narrower LUMO and HOMO gap and higher adsorption energy on zinc surfaces. These properties enabled theaflavins to be preferentially adsorbed onto zinc anode surfaces, forming a protective layer that minimized direct contact between water molecules and the zinc surface. This layer also promoted the electron transfer associated with zinc ions, thereby greatly enhancing interfacial stability and significantly mitigating HER. When 10 mmol/L of theaflavins was present in the electrolyte, the system exhibited lower impedance activation energy, a smoother zinc ion deposition process, reduced corrosion current, and higher HER overpotential. Furthermore, incorporating theaflavins into the electrolyte enhanced the vanadium redox reaction and accelerated zinc ion diffusion, thereby significantly improving battery performance. This work explores the design of a cost-effective electrolyte additive, providing essential insights for the progress of practical AZIBs. Full article

This paper presents a comparative mathematical analysis of electrode configurations used in active fog water harvesting systems based on electrostatic ionization. The study begins with a brief overview of fog formation and typology. It also addresses the global relevance of fog as a decentralized water resource. It also outlines the main methods and collector designs currently employed for fog water capture, both passive and active. The core of the work involves solving the Laplace equation for various electrode geometries to compute electrostatic field distributions and analyze field line density patterns as a proxy for potential water collection efficiency. The evaluated configurations include centered rod–cylinder, symmetric parallel multi-rod, and asymmetric wire–plate layouts, with emphasis on identifying spatial regions of high field line convergence. These regions are interpreted as likely trajectories of charged droplets under Coulombic force influence. The modeling approach enables preliminary assessment of design efficiency without relying on time-consuming droplet-level simulations. The results serve as a theoretical foundation prior to the construction of electrode layouts in the portable HygroCatch experimental harvester and provide insight into how field structure correlates with fog water harvesting performance. Full article

In exotic atomic systems with hadronic constituent particles, it is notoriously difficult to estimate the strong-interaction correction to energy levels. It is well known that, due to the strength of the nuclear interaction, the problem cannot be solved using Wigner–Brillouin perturbation theory alone. Recently, high-angular-momentum Rydberg states of exotic atomic systems with hadronic constituents have been identified as promising candidates in the search for new physics in the low-energy sector of the Standard Model. We thus derive a generalized Deser–Trueman formula for the induced energy shift for a general hydrogenic bound state with principal quantum number n and orbital angular momentum quantum number ℓ, and we find that the energy shift is given by the formula $\delta E=2{\alpha }_{n,\ell }{\beta }_{\ell }{(a_h/a_0)}^{2\ell +1}{E}_h/n^3$, where ${\alpha }_{n,0}=1$, ${\alpha }_{n,\ell }={\prod }_{s=1}^{\ell }(s^{-2}-n^{-2})$, ${\beta }_{\ell }=(2\ell +1)/{[(2\ell +1)!!]}^2$, $E_h$ is the Hartree energy, $a_h$ is the hadronic radius and $a_0$ is the generalized Bohr radius. The square of the double factorial, ${[(2\ell +1)!!]}^2$, in the denominator implies a drastic suppression of the effect for higher angular momenta. Full article

This study presents a comprehensive numerical investigation of excitonic states in GaAs quantum wells embedded in ${\mathrm{Al}}_x$${\mathrm{Ga}}_{1-x}$As barriers, incorporating the effects of donor and acceptor impurities, external electric and magnetic fields, and varying well widths. The electron and hole wavefunctions are computed by directly solving the Schrödinger equation using the finite element method in cylindrical coordinates, without assuming trial forms. To evaluate the exciton binding energy, the implementation and comparison of two independent approaches were performed: a numerical integration method based on elliptic function corrections, and a novel finite element electrostatic formulation using COMSOL Multiphysics v5.6. The latter computes the Coulomb interaction by solving Poisson’s equation with the hole charge distribution and integrating the resulting potential over the electron density. Both methods agree within 1% and capture the spatial and field-induced modifications in excitonic properties. The results show that quantum confinement enhances binding in narrow wells, while donor impurities and electric fields reduce binding via spatial separation of carriers. Magnetic fields counteract this effect by providing radial confinement. The FEM-based electrostatic method demonstrates high spatial accuracy, computational efficiency, and flexibility for complex heterostructures, making it a promising tool for exciton modeling in low-dimensional systems. Full article

This study investigates the formation mechanism and stress response characteristics of normal faults in coal-bearing strata through large-scale physical simulation experiments. A multi-layer heterogeneous model with a geometric similarity ratio of 1:300 was constructed using similar materials that were tailored to match the mechanical properties of real strata. Real-time monitoring techniques, including fiber Bragg grating strain sensors and a DH3816 static strain system, were employed to record the evolution of deformation, strain, and displacement fields during the fault development. The results show that the normal fault formation process includes five distinct stages: initial compaction, fault initiation, crack propagation, fault slip, and structural stabilization. Quantitatively, the vertical displacement of the hanging wall reached up to 5.6 cm, equivalent to a prototype value of 16.8 m, and peak horizontal stress increments near the fault exceeded 0.07 MPa. The experimental data reveal that stress concentration during the fault slip stage causes severe damage to the upper coal seam roof, with localized vertical stress fluctuations exceeding 35%. Structural planes were found to control crack nucleation and slip paths, conforming to the Mohr–Coulomb shear failure criterion. This research provides new insights into the dynamic coupling of tectonic stress and fault mechanics, offering novel experimental evidence for understanding fault-induced disasters. The findings contribute to the predictive modeling of stress redistribution in fault zones and support safer deep mining practices in structurally complex coalfields, which has potential implications for petroleum geomechanics and energy resource extraction in similar tectonic settings. Full article

This study presents an integrated geomechanical modeling framework for predicting multi-scale fracture networks and their activity in the Longmaxi Formation shale reservoir, northern Luzhou region, southeastern Sichuan Basin—an area shaped by complex, multi-phase tectonic deformation that poses significant challenges for resource prospecting. The workflow begins with quantitative characterization of key mechanical parameters, including uniaxial compressive strength, Young’s modulus, Poisson’s ratio, and tensile strength, obtained from core experiments and log-based inversion. These parameters form the foundation for multi-phase finite element simulations that reconstruct paleo- and present-day stress fields associated with the Indosinian (NW–SE compression), Yanshanian (NWW–SEE compression), and Himalayan (near W–E compression) deformation phases. Optimized Mohr–Coulomb and tensile failure criteria, coupled with a multi-phase stress superposition algorithm, enable quantitative prediction of fracture density, aperture, and orientation through successive tectonic cycles. The results reveal that the Longmaxi Formation’s high brittleness and lithological heterogeneity interact with evolving stress regimes to produce fracture systems that are strongly anisotropic and phase-dependent: initial NE–SW-oriented domains established during the Indosinian phase were intensified during Yanshanian reactivation, while Himalayan uplift induced regional stress attenuation with limited new fracture formation. The cumulative stress effects yield fracture networks concentrated along NE–SW fold axes, fault zones, and intersection zones. By integrating geomechanical predictions with seismic attributes and borehole observations, the study constructs a discrete fracture network that captures both large-scale tectonic fractures and small-scale features beyond seismic resolution. Fracture activity is further assessed using friction coefficient analysis, delineating zones of high activity along fold–fault intersections and stress concentration areas. This principle-driven approach demonstrates how mechanical characterization, stress field evolution, and fracture mechanics can be combined into a unified predictive tool, offering a transferable methodology for structurally complex, multi-deformation reservoirs. Beyond its relevance to shale gas development, the framework exemplifies how advanced geomechanical modeling can enhance resource prospecting efficiency and accuracy in diverse geological settings. Full article

Aqueous aluminum-ion batteries (AAIBs) face significant challenges due to interfacial instability and parasitic side reactions during the reversible deposition of aluminum. Here, we introduce a hybrid electrolyte incorporating triethyl phosphate (TEP), a non-flammable co-solvent that reconstructs the Al³⁺ solvation environment by suppressing water activity. This design extends the electrochemical stability window and enables uniform Al–Zn alloy formation at the anode interface. As a result, symmetric Al–Zn cells achieve over 4000 h of stable cycling. In full-cell configurations with V₂O₅/C cathodes, the system demonstrates high capacity retention (~96% over 450 cycles at 2 A g⁻¹) and coulombic efficiency. This work underscores the potential of solvation structure engineering via functional, flame-retarding co-solvent to advance the development of safe and durable aqueous electrolytes. Full article

Aqueous zinc-ion batteries (AZIBs) have gained significant attention as promising candidates for next-generation energy storage systems, especially in mobile robotics, due to their inherent safety, environmental friendliness, and low cost. However, the practical application of AZIBs is often hindered by slow Zn²⁺ diffusion and the poor structural stability of the cathode materials under high-rate or long-term operation. To address these challenges, a defect-engineered, binder-free MnO₂ electrode, with a MnO₂ loading of 1.35 mg·cm⁻², is synthesized via in situ hydrothermal growth of ultrathin MnO₂ nanosheets directly on a 3D conductive nickel foam scaffold, followed by reductive annealing to introduce abundant oxygen vacancies. These oxygen-rich defect sites significantly enhance Zn²⁺ adsorption, improve charge transfer kinetics, and contribute to enhanced pseudocapacitive behavior, further improving overall electrochemical performance. The intimate contact between the MnO₂ and Ni substrate ensures efficient electron transport and robust structural integrity during repeated cycling. With this synergistic architecture, the MnO₂@Ni electrode achieves a high specific capacity of 122.9 mAh·g⁻¹ at 1 A·g⁻¹, demonstrating excellent cycling durability with 94.24% capacity retention after 800 cycles and nearly 99% coulombic efficiency. This study offers a scalable strategy for designing high-performance, structurally stable Zn-ion battery cathodes with improved rate capability, making it a promising candidate for energy-intensive mobile robotic and flexible electronic systems. Full article

We review our recent findings on the structure and properties of exotic heavy hadrons, focusing on two main topics. First, we examine the role of correlations driven by the short-range Coulomb-like color interaction in hidden heavy-flavor pentaquarks. We show how this framework consistently accounts for the observed pattern of $P_c$ and $P_{cs}$ states in the hidden-charm sector and enables predictions for the hidden-bottom sector, where experimental data are still lacking. The second topic explores the possibility of forming stable multihadron molecules from deeply bound two-hadron exotic states. In this context, a bound state of three B mesons, denoted as $T_{bbb}$, with quantum numbers $\left(I\right)J^P=(1/2)2^{-}$, is presented. We find that the binding energy generally decreases as the number of hadrons increases, primarily due to effects of the Pauli principle and the appearance of new decay thresholds. Nonetheless, resonances may still arise in specific cases, depending on the internal thresholds of the system. Finally, we discuss how the decay width of an exotic multihadron resonance can offer valuable insights into its internal structure and underlying dynamics. Full article