Search Results (955)

This study reports a simple, high-performance, and cost-effective hydrovoltaic power generator driven by natural seawater. The device combines 3D porous non-woven fabrics with asymmetric copper–aluminum electrodes, offering flexible design and excellent environmental adaptability. The stochastic network of the non-woven fabric acts as an efficient ion-transport highway, accelerating electrolyte infiltration via its large surface area and strong capillary wicking. Leveraging the high ionic strength of seawater compresses the electrical double layers and minimizes internal resistance, boosting the short-circuit current by 25 times compared with deionized water. Short-circuit currents of ~60 μA and open-circuit voltages of ~650 mV were each maintained for over 1200 s. Systematic optimization shows that a 1 mm electrode spacing balances ionic transport and parasitic losses, delivering a peak power of 12.5 μW. Scalability is demonstrated by integrating multiple units: three parallel units scale the current to 173 μA, while three series units increase the voltage to 1500 mV, providing a practical strategy for sustaining low-power electronics. This work establishes non-woven fabric-based generators as a robust platform for harvesting energy from naturally abundant seawater, offering a practical and scalable design for next-generation self-powered small-scale devices. Full article

This study presents a high-efficiency T-type three-level inverter for interior permanent magnet synchronous motor (IPMSM) drive applications, featuring a comprehensive performance comparison with a conventional two-level inverter. To address the high switching losses and noticeable harmonic distortion typically associated with conventional two-level configurations, the T-type architecture is developed and evaluated. First, PLECS simulations are conducted to verify the proposed dual-loop control architecture, which integrates field-oriented control (FOC), space-vector pulse-width modulation (SVPWM), and a neutral-point voltage balancing mechanism. Subsequently, a 2.2 kW experimental platform is constructed using silicon carbide (SiC) wide-bandgap (WBG) semiconductor devices. To characterize the dynamic switching behavior of the adopted SiC MOSFETs, a dedicated double-pulse test (DPT) platform is developed to evaluate their switching losses and determine appropriate gate-drive parameters. In addition, the digital control firmware is implemented on a digital signal processor (DSP) platform. The dual-loop control algorithms, SVPWM strategy, and two-layer protection framework are implemented as real-time executable routines, enabling close integration of the control software and hardware platform. Finally, motor drive experiments at switching frequencies of 20 kHz and 40 kHz are performed to validate the proposed system. The experimental results demonstrate that the developed architecture significantly reduces phase-current total harmonic distortion (THD) and improves overall energy conversion efficiency compared with a conventional two-level inverter, confirming its potential for high-efficiency next-generation electric vehicle applications. Full article

Wireless power transfer has become an increasingly widespread technology in electric vehicle and charging-system applications. Advances in power electronics have led to significant improvements in system efficiency, and in parallel, extensive research has been conducted on energy storage technologies and coil designs. In this study, a split-coil structure using a dual inverter system is analyzed, aiming to achieve a flatter magnetic-flux distribution for electric vehicle charging systems and battery energy storage circuits or an increase in total flux density for power applications. A flatter flux distribution will make a significant improvement in electric vehicle charging systems under misalignment conditions. The key point based on these concepts is the dually driven split coil, which is analyzed as both a single-layer and a double-layer coil. The main objective of the present study is to investigate the magnetic-flux distribution and the performance of the proposed fully symmetric two-layer coil structure under nominally aligned conditions. Owing to the fully symmetric geometry, the presented one-dimensional magnetic-flux scan is sufficient for comparing the flux-distribution characteristics of the proposed and conventional coil structures. Following the demonstration that the single-layer split coil design was ineffective, theoretical analyses and experimental data indicate that the double-layer split-coil design provides 10% higher efficiency. Full article

We propose and demonstrate, for the first time, a sandwich structure of graphene substrates, pyrene derivatives, and an electrolyte for ultraviolet light sensing. A contact capacitor forms at the graphene–electrolyte interface via the electric double layer. When ultraviolet light excites the interlayer of the pyrene derivative, a photo-generated electric field changes the carrier density in graphene, affecting its conductivity. Thus, the sandwich structure responds to ultraviolet light intensity, which is monitored by current changes in different states. Linear fitting shows a strong positive relationship between UV intensity and current (Ids), with R² above 0.99 and excellent reproducibility. The responsivity (R) and response time (τ_r) for the measurement at a distance of 50 cm are estimated as 0.7 A/W and 70 s, respectively. Full article

Flexible pressure sensors serve as core sensing components for wearable health monitoring systems, electronic skins for soft robots, and flexible human–machine interaction devices. Benefiting from the interfacial electric double-layer polarization effect, iontronic sensing delivers far higher pressure response sensitivity than conventional parallel-plate capacitive sensors, endowing it with distinctive advantages in the detection of weak physiological signals. Nevertheless, current dense ionic thin-film dielectric layers suffer from limited deformation space under compression and poor low-pressure sensing capability. Mainstream high-precision micropillar arrays are fabricated via photolithography, 3D printing, and metal etching molds, which require costly equipment and complicated fabrication procedures, making large-area mass production unfeasible. Random frosted concave-convex microstructures feature disordered dimensions, leading to severe device hysteresis and narrow linear ranges, which fail to achieve ultrahigh sensitivity alongside a wide pressure detection range simultaneously. To address the aforementioned multiple bottlenecks, this paper proposes a low-cost resin template replication process to fabricate TPU-based ionic thin-film dielectric layers with ordered micropillar array microstructures. Combined with inkjet-printed silver conductive PI flexible electrodes, an iontronic flexible pressure sensor with a sandwich layered structure is constructed. Multi-dimensional investigations including microscopic morphology characterization, electromechanical sensing performance calibration, and human wearable application tests are systematically implemented to thoroughly elucidate the synergistic enhancement mechanism of the arrayed micropillars. Test results demonstrate that the effective pressure detection range of the sensor spans 0–1038 kPa, accommodating ultra-low pressures such as pulse signals as well as medium-to-high-pressure loads including joint bending. The sensitivity reaches 23.27 kPa⁻¹ within the low-pressure range of 0–200 kPa and remains stable at 3.52 kPa⁻¹ in the high-pressure range of 200–1038 kPa, with piecewise linear fitting correlation coefficients of 0.93 and 0.96 respectively. Both the response time and recovery time of the device are 40 ms, and the hysteresis error throughout the loading-unloading cycle is merely 2.62%. After 20,000 consecutive cyclic loading-unloading tests, the peak capacitance output only decays by 5.1%, verifying outstanding mechanical fatigue resistance and electrical stability. Validations in multi-scenario applications prove that the sensor can accurately capture human physiological and motion signals including radial artery pulses, laryngeal deformation induced by multi-syllable vocalization, and multi-angle bending of fingers and elbow joints, suitable for home-based health monitoring, quantitative rehabilitation training, flexible tactile interaction and other scenarios. The entire fabrication process eliminates high-precision micro-nano processing equipment such as photolithography systems, plasma etchers and 3D printers; only general chemical raw materials and conventional laboratory instruments are adopted. The reusable templates enable low manufacturing costs and large-area coating forming, offering a novel low-cost technical solution for the engineering implementation and industrialization of high-performance iontronic flexible pressure sensors. Full article

Marine concrete structures are subjected to multiple aggressive ions that react with hydration products, driving dynamic phase evolution and altering ion transport pathways. This study develops a multi-scale lattice diffusion–reaction coupled framework grounded in a microstructural evolution model, incorporating a simplified analytical correction for the electrical double layer (EDL) effect. Validation against Poisson–Boltzmann numerical solutions across a pore size range of 1.5–50 nm confirms that the mean relative errors for monovalent, divalent, and trivalent ions remain within 10%. The phase evolution of cement paste under single-ion attack was simulated, and its impact on ion transport performance under multi-ion coupled ingress was systematically investigated. Under multi-ion attack, solid phases exhibit a highly ordered spatial zonation. Chloride ions completely displace monosulfate, forming a Friedel’s salt-enriched zone. Meanwhile, directly penetrating external sulfate generates a pronounced surface ettringite peak, while sulfate released from monosulfate decomposition in the Friedel’s salt zone induces secondary ettringite precipitation deeper within the material, producing a characteristic double-step ettringite distribution. A cracking criterion based on the critical capillary pore filling fraction captures the transition from pore filling to microcracking, yielding a three-zone profile for the relative diffusion coefficient. At 500 days of exposure, crystallization-induced microcracking triggers a more than 7-fold increase in surface relative diffusivity ($w/c$ = 0.35). Furthermore, at 250 days, once cracking initiates, low water-to-cement ratio ($w/c$ = 0.3) matrices display a higher relative diffusivity amplification factor of approximately 9, compared to approximately 6 for high water-to-cement ratio ($w/c$ = 0.4) matrices. The established framework provides a quantitative tool for assessing the durability of concrete structures under complex chemical attack environments. Full article

Aqueous zinc-ion batteries (AZIBs) are promising for scalable energy storage, yet their practical viability is constrained by zinc dendrite propagation, parasitic hydrogen evolution, and interfacial corrosion. Formulating electrolyte additives represents an economically viable strategy to address these long-standing bottlenecks by modulating the bulk solution and double-layer environments. Diverging from traditional composition-based classifications, this review categorizes recent additive strategies according to their underlying physical chemistry mechanisms. Specifically, we evaluate how these additives regulate the primary and secondary Zn²⁺ solvation sheaths, reconstruct the electric double layer (EDL) for crystallographic facet control, induce sacrificial or mineralized solid electrolyte interphases (SEIs), and establish responsive polymer confinement networks. Furthermore, we critically discuss the operational limitations, trade-offs, and parameter dependencies of these strategies under non-ideal, realistic conditions. Finally, prospective directions are outlined—focusing on descriptor-driven design, operando non-equilibrium characterizations, and performance validation under standard industrial metrics (e.g., low E/C ratios and high depths of discharge)—to provide an objective framework for advancing electrolyte optimization in practical zinc-based energy storage. Full article

Constructed wetlands (CWs) are widely used as an ecological technology for wastewater treatment. However, the accumulation of microplastics (MPs) in their substrates may impair long-term performance and threaten the operational sustainability of these nature-based treatment systems. To elucidate the transport behaviour of MPs in wetland substrates, this study developed a numerical model based on the lattice Boltzmann method (LBM) to simulate advection, hydrodynamic dispersion, and reversible first-order adsorption/desorption of MPs in saturated porous media. The model incorporates a salinity-dependent non-linear attachment rate coefficient, which captures the compression of the electrical double layer and the enhanced attachment efficiency with increasing salinity. Pore-scale flow is solved using the LBM with an Ergun-type drag term to represent the resistance of the porous matrix. The model was validated against experimental breakthrough curves from column studies using quartz sand and coastal wetland soils under five salinity levels (0–35 PSU) reported in the literature. Quantitative validation yielded coefficients of determination (R²) ranging from 0.782 to 0.960 (RMSE = 0.024–0.045) for calibration cases and 0.741 to 0.946 (RMSE = 0.027–0.048) for independent validation cases across both substrates, excluding the soil cases at 3.5 and 35 PSU. Here, both observed and simulated effluent concentrations were identically zero, resulting in the statistically forced R² = 1.000 and RMSE = 0, which are mathematical artefacts rather than indicators of predictive performance. The simulations reproduce the observed reduction in peak relative concentration by over 50% in sand and near-complete retention (C/C₀ ≈ 0) in soil at high salinities (3.5 and 35 PSU). Results demonstrate that the model successfully reproduces the differences in MP breakthrough behaviour across different substrate types and salinity levels. By linking salinity-enhanced retention to the risk of irreversible clogging and shortened wetland lifespan, the model provides a predictive tool for evaluating the sustainability of CWs under saline stress. This study offers a scientific basis for optimizing hydraulic management (e.g., flushing strategies) to mitigate microplastic pollution and enhance the long-term sustainability and resilience of constructed wetlands in coastal and saline environments. Full article

To overcome the limitations of insufficient driving force in traditional microbial desalination batteries, this paper constructs a microbial anode-membrane capacitive deionization (B-MCDI) coupling system. For the first time, direct coupling between extracellular electron transfer in Shewanella oneidensis and double-layer adsorption at the MCDI cathode is achieved at the circuit and material levels, realizing self-driven, low-energy desalination. High-specific-surface-area carbon felt is used as the anode, and a stable electrogenic biomembrane (output voltage >400 mV) is formed after directional domestication with Shewanella oneidensis MR-1. Activated carbon is used as the cathode to construct the MCDI electrode. In the three-chamber reactor, the desalination chambers are separated by cation and anion exchange membranes. Under the drive of the bioelectric field, Na⁺ and Cl⁻ selectively permeate into the cathode and anode chambers, respectively, effectively suppressing the co-ion effect. Under optimal operating conditions (external resistance 1000 Ω, initial NaCl concentration 2.0 g/L), the system achieved a cumulative desalination rate of 85.1% after 12 h of operation, with a salt adsorption capacity of 162.1 mg/g, an average desalination rate of 13.51 mg/(g·h), and an energy consumption of only 0.58 kWh/m³. This demonstrates that bioelectric energy can effectively provide targeted power to drive capacitive adsorption and desalination. Under initial NaCl concentrations of 1.0 g/L and 3.0 g/L, the highest desalination rates reached 78% and 68%, respectively. The maximum instantaneous desalination rate occurred within 0.5–1.0 h (64 mg/h under 2.0 g/L conditions), exhibiting a three-stage kinetic characteristic of “fast-slow-equilibrium”. The energy consumption in this study was only 0.51 kWh/m³, further demonstrating the high energy efficiency of bioelectrically coupled MCDI in low-salinity treatment areas. Therefore, this B-MCDI can serve as a theoretically feasible proof-of-concept technology for desalination of brackish water that meets the requirements of self-driven, low-energy consumption, and has promising applications in decentralized water supply systems in areas with limited energy supply or no available electricity. Full article

To solve the conflict between trajectory tracking and stability control for distributed drive electric vehicles under complex driving conditions, an integrated longitudinal and lateral coordinated control strategy based on a hierarchical architecture is proposed in this paper. First, a stability-boundary dataset is constructed using an improved sum-of-squares programming (ISOSP) algorithm. Then, a long short-term memory (LSTM) network is optimized with the sparrow search algorithm (SSA). Finally, a prediction model is established to identify the dynamic stability region in real time. A hierarchical architecture is adopted for the control strategy. The upper layer integrates longitudinal–lateral tracking and stability control to describe the desired motion states accurately. In the middle layer, a stability margin is defined based on the stability region, and a risk factor is introduced to reconstruct the optimization objective. Through this design, the coordinated control of trajectory tracking and vehicle stability is achieved. In the lower layer, the minimization of the tire-workload rate is taken as the objective, and the optimal allocation of four-wheel torque is realized through quadratic programming. Hardware-in-the-loop (HIL) tests based on an NI PXIe-1078 real-time simulator, a host computer, and a domain controller indicate that the proposed strategy achieves good control performance under both variable-speed high-adhesion and high-speed low-adhesion double lane change (DLC) conditions. Especially in the extreme condition of high speed and low adhesion, the root-mean-square errors (RMSEs) of lateral displacement and sideslip angle are controlled within 0.4125 m and 0.0365 rad, respectively. Consequently, the high-precision tracking capability and real-time stability maintenance of the coordinated control strategy under extreme conditions are successfully verified. Full article

The electric double layer (EDL) at the copper/polyethylene (Cu/PE) interface critically affects space charge injection and insulation performance of high-voltage cables and their accessories, yet its molecular-level regulation remains unclear. This study systematically investigates the effects of different EDL structures on the potential distribution and interfacial barrier at the Cu/PE interface using first-principles calculations. The results show that the EDL-induced built-in electric field significantly modulates the potential of the PE layer, while the Cu layer remains largely unaffected. When the Cu side is positively charged and PE negatively charged, the EDL increases the interfacial barrier, suppressing charge injection and restricting PE molecular diffusion. Conversely, an EDL with negatively charged Cu and positively charged PE lowers the barrier, promotes charge injection, and enhances the diffusion of PE molecules. Notably, Na-induced EDL enhances PE diffusivity, whereas F-induced EDL restricts molecular motion. This work elucidates the regulatory mechanisms of EDL on both electronic and kinetic properties at the Cu/PE interface, providing a theoretical foundation for improving high-voltage cable insulation. Full article

Conductive polymer composite (CPC)-based wearable electronics and flexible strain sensors work in different environments, which require CPCs to show stable electrical performance at a wide range of temperatures. However, the resistance of most CPCs is generally temperature-dependent. In this work, a double-layer conductive framework was fabricated by coating highly conductive poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on a graphene mesh. The resulting composite, PEDOT:PSS/GM/PDMS-0.75, exhibited outstanding conductivity (8.1 S/cm), a high gauge factor (~42), excellent reliability (1000 cycles) and stable sensing performance within −30~140 °C. This work highlights the importance of PEDOT:PSS in improving the conductive stability of graphene-based strain sensors at different temperatures. Moreover, applications of sensing for human joint movement in different environments open new opportunities for temperature-insensitive CPCs. Full article

In this paper, the concept of symmetry is applied to design active trajectory tracking control of autonomous distributed drive electric vehicles considering energy efficiency—that is, the construction and solution of active trajectory tracking controllers are symmetrical. This paper proposes a hierarchical control strategy consisting of upper-level control and lower-level control to improve trajectory tracking accuracy of DDEVs considering energy-efficiency characteristics. In the upper-layer control, a sliding mode active disturbance rejection (ADRC) controller is developed to control the front wheel steering angle and active yaw moment to achieve tracking of the desired trajectory, in which an extended state observer (ESO) is synthesized to estimate and compensate for internal model uncertainties and external environmental disturbances. In the lower-layer control, a multi-objective optimization algorithm based on Karush–Kuhn–Tucker (KKT) conditions is designed to realize the torque distribution control for improving energy efficiency and vehicle stability of the distributed drive electric vehicle. Finally, a joint simulation platform based on Matlab/Simulink-CarSim (version 2019) is established for simulation verification. The performances of ADRC, linear quadratic regulator controller (LQR), and model predictive controller (MPC) are compared in snake-like and double-lane-change maneuvers. Simulation results show that the proposed controller can effectively reduce motor energy consumption while maintaining trajectory tracking accuracy and handling stability. This work provides a certain engineering design solution for motion control of intelligent electric vehicles. Full article

Developing tire sealants that effectively combine rapid sealing and mechanical durability remains a key challenge. This study presents a novel, high-performance sealant based on a natural rubber latex (NRL) matrix reinforced with uniformly dispersed hydrophobic nano-silica (SiO₂). A stable and homogeneous composite was achieved by employing sodium dodecylbenzene sulfonate (SDBS) as a surfactant and using ultrasonic processing. In simulated puncture tests, the optimized composite demonstrated superior performance, reducing the critical repair distance by approximately 3 km and the tire pressure loss by more than 75% compared to the reference samples. The repair mechanism was investigated through rheological analysis, electron microscopy, and mechanical testing. The enhanced performance correlates with electrical double-layer compression and particle aggregation and is accompanied by increased storage modulus and viscosity recovery that contribute to the sealing efficiency. These effects collectively increase the sealant’s storage modulus, enabling rapid sealing and effective resistance to shear under mechanical loading during tire rotation. This work provides both a practical formulation strategy and mechanistic insight for the development of next-generation, high-performance tire puncture sealant. Full article

Magnesium alloys are used or considered for lightweight structures and biodegradable implants, but high electrochemical activity, limited wear resistance, and localized corrosion still limit their service reliability. Plasma electrolytic oxidation (PEO), also called micro-arc oxidation (MAO), forms an adherent ceramic scaffold. Discharge channels, interconnected pores, thermal cracks, and a mechanically weak outer layer mean that the as-formed coating is rarely a complete protective system. This review examines advanced PEO/MAO-based composite coatings through a process–structure–function lens and develops an application-oriented design framework. The discussion covers PEO/MAO process-window control, electrolyte and particle engineering, sol–gel and polymer sealing, layered double hydroxide/inhibitor systems, self-healing reservoirs, superhydrophobic and slippery interfaces, Ca-P/hydroxyapatite and polymer biofunctionalization, and duplex coatings for wear, electrical, and thermal functions. Emphasis is placed on how these modules regulate defect connectivity, mass transport, interfacial stability, damage response, tribocorrosion, and biodegradation, as well as on the evidence needed to support each claimed function. The analysis indicates that coating performance is governed not by multilayer complexity alone, but by the compatibility among the ceramic scaffold, functional module, dominant failure mode, and service-specific validation protocol. Chloride-exposed structures require durable pore sealing and active inhibition; wear-critical components require coupled corrosion–wear assessment; and biodegradable implants require a degradation window that balances corrosion moderation, cytocompatibility, biofunctionality, and residual mechanical integrity. Remaining challenges include interfacial durability, finite inhibitor reservoirs, wetting-state instability, process reproducibility, scale-up, and life-cycle impacts. The proposed process maps and validation criteria are intended to support modular, testable, and application-specific PEO/MAO surface systems for magnesium alloys. Full article