Substrate-modulated interfacial proton adsorption on graphene.

NbFeSb thermoelectric materials require ultrahigh carrier concentrations (∼1021 cm-3) to optimize their electrical transport properties due to their high density-of-state effective mass, yet the heavy doping-induced atomic radius mismatch disrupts lattice potentials, degrading carrier mobility while simultaneously enhancing point defect and phonon scattering, creating a critical trade-off between electronic and phononic performance optimization. This work optimizes the thermoelectric performance of Ta-doped NbFeSb-based half-Heusler alloys via the lanthanide contraction effect. The Nb0.82-xTaxTi0.06Zr0.06Hf0.06FeSb (x = 0-0.25) alloys, synthesized through levitation melting and spark plasma sintering, exhibit exceptional room-temperature electrical conductivity (5000 S cm-1) and carrier concentrations (2 × 1021 cm-3). Ta doping enhances mass fluctuation scattering, reducing the lattice thermal conductivity by 24% while maintaining high power factors of 40 μW cm-1 K-2 across temperatures. The x = 0.1 composition achieves a peak zT of 0.8 at 973 K while maintaining excellent room-temperature electrical transport properties that are crucial for low-ΔT applications. Leveraging this material, a wearable thermoelectric wristband integrating 40 × 8 p-n modules (NbFeSb/ZrNiSn) was designed. Finite element simulations under ΔT = 16 °C demonstrate a maximum output power of 15.6 μW. Furthermore, the output power shows a positive correlation with the applied temperature gradient, highlighting its adaptability. This work highlights the synergy between lanthanide contraction-driven material optimization and device engineering, offering a robust solution for high-performance wearable thermoelectric applications.

Metallic delafossite PdRhO2 thin films were synthesized using a low-rhodium solution deposition strategy, achieving epitaxial growth despite a significant lattice mismatch. Comparative structural and electrical transport analyses demonstrate that reducing the lattice mismatch significantly improves both film quality and electrical performance. First-principles calculations reveal that the metallic conductivity in PdRhO2 originates primarily from Pd-derived states and their hybridization with Rh 4d orbitals at the Fermi level. Furthermore, a PdRhO2/β-Ga2O3 Schottky heterojunction was fabricated, exhibiting a rectification ratio on the order of ∼109 and a Schottky barrier height of 1.13 ± 0.06 eV. This barrier height exceeds the prediction of the Schottky–Mott rule, which is attributed to a naturally formed interfacial dipole layer. These findings offer a cost-effective pathway to epitaxial Rh-based thin films and highlight their potential for application in electronic integrated circuits.

We report the observation of an unexpected phase transition at high magnetic fields between the spin-flop and spin-flip transitions in the d-electron antiferromagnetic metal V5S8. High-precision magnetic, thermal and electrical transport measurements enable the transitions to be tracked up to fields as high as 35 T and at temperatures down to the milli-kelvin range revealing three distinct magnetic quantum phase transitions. We present a model that finds agreement with our observation of a triad of spin transitions involving two sublattices with frustrated inter-and intra-sublattice spin couplings.

CaTiO3-based compounds have emerged as promising thermoelectric materials due to their environmental benignity, thermal stability, and cost-effectiveness. However, the strong polar character of the metal-oxygen bonds imposes a fundamental limitation on the electrical conductivity, thereby restricting the overall thermoelectric performance. Herein, we demonstrate that defect engineering could induce synergistic effects, manifested in (i) a weakness of chemical bond polarity, which significantly enhances carrier mobility from ∼4.9 to ∼25.1 cm2 V-1 s-1 at 600 K. (ii) the introduction of substantial lattice distortions and strain, effectively suppressing the lattice thermal conductivity. (iii) a softened crystal lattice to further suppress phonon propagation. Consequently, a peak ZT value of 0.35 is acquired for Ca0.85Nd0.15Ti0.95Nb0.05O3 at 1073 K, approximately 337.5% higher than that of the pristine CaTiO3 sample. Our investigation provides insights into how aliovalent doping can simultaneously modulate electrical and phonon transport properties, contributing a valuable design principle to the field of thermoelectrics.

The electrification of transport is vital to achieving global climate targets, with electric vehicles (EVs) positioned as a sustainable alternative to fossil fuel–based mobility. However, the scalability of EV adoption hinges on the accessibility, reliability, and user experience of public charging infrastructure. As China leads the world in EV adoption, Shanghai represents a critical case for evaluating user satisfaction in a megacity context where infrastructure density, urban planning, and consumer behavior intersect. Despite significant investments in expanding charging facilities, limited empirical research has examined how users perceive and interact with Shanghai’s public EV charging network. This study addresses that gap through a quantitative, user-centered analysis of responses from 197 EV users using the QUESS-PAC framework (Quantitative User Experience Survey Strategy for Public EV Charging Analysis in Cities). A structured questionnaire assessed satisfaction across multiple dimensions: infrastructure layout, convenience, pricing, ease of use, safety, and lighting. Using SPSS (v28), descriptive analysis and multiple regression were conducted to identify key determinants of satisfaction. The findings indicate low overall user satisfaction, with critical weaknesses in location planning, cost transparency, and interface usability. Regression analysis highlights four significant predictors of satisfaction—layout, ease of use, pricing, and lighting—with charging price emerging as the most influential factor. This study’s unique contribution lies in the development and application of the QUESS-PAC framework, which integrates quantitative UX metrics with behavioral and spatial dimensions to provide a more systematic assessment than prior descriptive studies. It emphasizes the need for integrated planning that combines spatial equity, service design, and behavioral insights. Based on the analysis, policy recommendations are proposed to enhance satisfaction and encourage adoption. These findings offer transferable insights for global cities navigating the electrification of transport.

Abstract This article explores the electric field-dependent spin transport in (NiFe, Co)/PVDF(120 nm)/Fe3O4 multiferroic spin valve junctions (MFSVJs) by modulating the electric polarization of PVDF and its corresponding interfacial potential barriers. This approach enables to realize four distinct and stable resistance states at room temperature, a critical feature for spintronic device applications aiming for low-power and higher data storage capacity. Quasi-static current-voltage and dynamic polarization - electric field measurements reveal the formation of an additional Schottky-type barrier at the PVDF/Fe3O4 interface during the upward polarization state of PVDF, attributed to modifications in the electrostatic potential. The presence of this Schottky barrier under upward polarization and its absence under downward polarization, enhances asymmetry within the MFSVJs, significantly affecting both charge and spin transport properties, which further evolve with varying electric field amplitudes. Further, both electroresistance (ER) and electro-magnetoresistance (EMR) are found to increase with decreasing junction areas and a notable ER of +133% and EMR of +141% are observed in a NiFe/PVDF/Fe3O4 MFSVJ with a junction area of 0.5 mm2.

Defect-induced bandgap modification and electrical transport in Cu-doped CoWO4 systems

Phosphate compounds are promising for next-generation optoelectronic and electronic applications due to their versatile structures and properties.

Investigation and evaluation of strategic residential heat and transport electrification for supporting deep grid decarbonization

Assessing decarbonization benefits of transport electrification: A provincial perspective in China

Abstract This study investigates, for the first time in the literature, how substituting MWCNTs affects the structural, microstructural, electrical, and magnetic properties of single-crystal FeTe 0.5 Se 0.5 alloy. The MWCNTs were integrated into Fe sites in single crystalline Fe 1₋x (MWCNT) x Te 0.5 Se 0.5 (x = 0%–5%). One of our key findings is that MWCNTs dissolve well in the FeSeTe matrix up to a 4% substitution level, but beyond 3%, they appear as impurity phases within the structure. The electrical transport properties improved with increasing substitution, reaching their peak at 3%, but declined with further substitution, transforming the structure into a fully non-conductive form. The best electrical performance was obtained for the x = 3% sample with T on and T c values of 16.5 K and 15.6 K, respectively. This corresponds to a 1.7 K improvement in T c value compared to the x = 0% sample. The J c value was calculated as 1.4 × 10 5 A/cm 2 for the x = 0% and 1.1 × 10 6 A/cm 2 for the x = 3% sample, indicating a significant improvement of ~ 9.5 times. Similar improvement was also observed for the pinning force property, with F p = 2.15 × 10 6 N/m 3 for the x = 0% and F p = 4.91 × 10 7 N/m 3 for the x = 3% sample, indicating an improvement of more than 20 times. The H c2 (0) values increased with higher MWCNTs content, with the maximum H c2 (0) calculated as 78.1 T for the x = 3% sample. A notable decrease in U 0 / k B occurs as both the substitution rate and the applied field increase. This decline supports the idea that the thermally activated dissipation mechanism and independent vortex mobility are at play.

Bi<sub>2</sub>Te<sub>3</sub>-based materials prepared by traditional zone melting often suffer fro m poor mechanical properties. Although powder metallurgy followed by hot ext rusion can effectively enhance mechanical strength, this approach involves a len gthy, multi-step processes including powdering, sintering, and extrusion. Such a complex procedure has hindered the development of polycrystalline Bi<sub>2</sub>Te<sub>3</sub>-bas ed materials and their application in micro-thermoelectric devices. In this work, p-type Bi<sub>2</sub>Te<sub>3</sub>-based ribbons were first fabricated via melt spinning. Subsequent ly, a series of highly textured, fine-grained p-type Bi<sub>2</sub>Te<sub>3</sub>-based bulk materials were prepared by directly tiling these ribbons and consolidating them through Spark Plasma Sintering (SPS). The as-spun ribbons possess a strong texture, al ong with abundant nanostructures and defects. The subsequent consolidation, ac hieved by directly tiling these ribbons and applying Spark Plasma Sintering (SPS) without any pulverization, effectively preserved their intrinsic preferred orie ntation. This resulted in a strong (1 1 0) texture perpendicular to the pressing direction, which is distinct from that obtained via the conventional ball-milling and SPS route. The sample sintered at 743 K exhibited an orientation factor of 0.37, comparable to that of hot-extruded counterparts. Owing to this strong te xture, the sample exhibited superior electrical transport properties along the dire ction parallel to the pressure. A high power factor of 3.79 mW m<sup>-1</sup> K<sup>-2</sup> was ac hieved at room temperature. Furthermore, grain refinement led to a significant reduction in thermal conductivity. Consequently, a peak <i>ZT</i> value of 1.30 was obtained at 398 K for the sample sintered at 743 K, representing a 46% enhan cement over traditional zone-melted samples. This study provides a rapid and f acile strategy for fabricating highly textured, fine-grained, high-performance Bi<sub>2</sub> Te<sub>3</sub>-based materials, laying a solid foundation for their engineering applications in Micro-thermoelectric devices.

Experimental investigation of fuel cell system operational parameters for powertrain sizing and energy management in light commercial fuel cell electric transporters

Analysis of Advanced Nonisolated Topologies for Vehicle-Integrated Photovoltaic (ViPV) Systems in Urban Electric Transport Buses

Interfacial-engineered 3D nano-carbon networks for synergistic enhancement of thermal–electrical transport and anisotropic heat dissipation

Organic–inorganic hybrid perovskites have emerged as promising next-generation materials for high-performance optoelectronic devices due to their structural tunability and versatile physical properties. In this work, bis(triethylammonium) chlorocuprate(ii), [(C2H5)3NH]2CuCl4 was successfully synthesized via a slow evaporation method. The crystal structure, morphology, and optical and electrical properties of [(C2H5)3NH]2CuCl4 were systematically investigated using powder X-ray diffraction (PXRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS), Raman spectroscopy, UV-visible spectroscopy, and complex impedance spectroscopy. PXRD analysis reveals that the compound crystallizes in a monoclinic system with a centrosymmetric P21/c space group at room temperature. SEM observations show uniformly distributed grains with an average size of approximately 17.5 µm, separated by well-defined grain boundaries, while EDS analysis confirms the expected elemental composition, indicating successful synthesis of the hybrid material. Raman spectroscopy confirms the coexistence of vibrational modes characteristic of both the organic and inorganic components. Optical absorption measurements recorded in the 200–800 nm range reveal a wide direct band gap of approximately 2.36 ± 0.004 eV, characteristic of semiconducting hybrid perovskites. Electrical investigations demonstrate that the AC conductivity follows Jonscher's universal power law, indicating a thermally activated charge transport process over the investigated frequency range. Moreover, the temperature dependence of the frequency exponent s reveals that the correlated barrier hopping (CBH) model governs the electrical conduction mechanism in the studied material. Furthermore, complex modulus analysis provides additional insight into the relaxation behavior and the dominant electrical transport mechanisms.

Nb2SiTe4, a representative two-dimensional (2D) ferroelastic semiconductor, becomes research focus due to its high carrier mobility, ambipolar carrier transport, exceptional ferroelasticity and third harmonic generation response, rendering potential applications in ambipolar transistors, mid-infrared (MIR) detection, controllable electronic devices and tunable anisotropic all-optical devices. In this work, high-pressure lattice vibrational and electrical transport characteristics of Nb2SiTe4 were comprehensively explored up to 37.1 GPa using a diamond anvil cell (DAC) in conjunction with in situ Raman spectroscopy and electrical conductivity measurements in different hydrostatic environments. Upon non-hydrostatic pressurization, Nb2SiTe4 underwent metallization at 5.5 GPa owing to the rapid compression of the interlayer distance, followed by an electronic transition at 21.6 GPa triggered by the enhanced electron-phonon coupling. Nevertheless, the metallization and electronic transition of the specimen were delayed by ∼2.0 GPa under hydrostatic conditions due to the influence of deviatoric stress. Upon decompression to ambient conditions, the resumable Raman spectra and semiconducting characteristics elucidated the reversibility of the phase transition with the existence of residual stress in different hydrostatic environments. Our systematic high-pressure research studies on Nb2SiTe4 not only advance the in-depth understanding of its physicochemical behaviours in other 2D ferroelastic semiconductors but are also beneficial in steering its underlying applications in electronic and photonic devices.

Defects have been shown to play a significant role in the regulation of the mechanical properties of Al2Cu, and their impact on transport properties cannot be disregarded. In this paper, the effects of vacancy defects and substitutional defects on the transport properties of θ-Al2Cu and were systematically investigated based on the non-equilibrium Green's function combined with density functional theory. The results demonstrate that the transport properties of θ-Al2Cu are superior to those of . For the θ-Al2Cu system, the formation energy of Al vacancies is lower than that of Cu vacancies, indicating that Al vacancies are more likely to form. Nevertheless, Al vacancies cause a greater reduction in conductance than Cu vacancies. Therefore, the generation of Al vacancies should be minimized for practical applications. The influence of substitutional defects on transport properties is contingent on the matching degree in the atomic radii and chemical bonding properties between dopant atoms and host atoms. Impurity atoms with large differences in size or chemical bonding properties have been shown to enhance local potential barriers and electron scattering, thereby reducing transport performance. Besides, low-symmetry structures exhibit heightened sensitivity to such disturbances. Consequently, θ-Al2Cu could be a promising candidate for interconnect applications, provided Al vacancies are controlled and substitutional dopants are selected for minimal size and bonding disruption.

BACKGROUND.Despite the active development of electric transport, transient operating modes of electric drives in wheeled self-propelled machines remain insufficiently studied, especially under real-world operating conditions. AIMS:The purpose of this work is to develop experimental research methods for electric wheeled self-propelled vehicles in transient conditions and real-world operating conditions, as well as to establish patterns of influence of design and operational parameters on drive characteristics (using the example of a category AII self-propelled vehicle). METHODS.The experimental studies were carried out on a category AII electric self-propelled machine equipped with a series-wound DC motor and a four-speed gearbox. The tests included acceleration on different gears under varying degrees of accelerator pedal depression and with different load conditions. All parameters were recorded using digital measuring instruments and a high-speed video camera. The studied parameters included motor current, voltage at the battery and motor terminals, motor speed, and acceleration time. RESULTS.As a result of the experimental studies, patterns of the influence of gear ratios, the mass of a self-propelled vehicle and the longitudinal slope of the road on the electromechanical characteristics of the drive were established. The experimental data obtained are presented in the form of graphs of the dependence of current strength on time during acceleration in a fixed-length section: with maximum pressure on the accelerator pedal, with partial (50%) pressure on the accelerator pedal, and also when accelerating to a fixed speed with an empty and fully loaded cabin. Critical operating modes of the drive were also identified, characterized by high amperage values, with sudden acceleration at elevated gears III and IV and upward movement. CONCLUSION.The results confirm the high sensitivity of drive performance to external factors and justify the application of the developed methodology for validating mathematical models and optimizing the design of electric drives for self-propelled machines.