Search Results (243)

The increasing adoption of electric vehicles has driven the development of charging technologies that meet growing demands for power, efficiency, and grid compatibility. This review presents a comprehensive analysis of the EV charging ecosystem, covering Level 3 DC charging stations, power converter topologies, and the role of energy storage systems in supporting grid integration. Commercial solutions and academic prototypes are compared across key parameters such as voltage, current, power, efficiency, and communication protocols. The study highlights trends in charger architectures—including buck, boost, buck–boost, LLC resonant, and full-bridge configurations—while also addressing the integration of stationary storage as a buffer for fast charging stations. Special attention is given to wide-bandgap semiconductors like SiC and GaN, which enhance efficiency and thermal performance. A significant gap persists between the technical transparency of commercial systems and the ambiguity often observed in prototypes, highlighting the urgent need for standardized research reporting. Although converter efficiency is no longer a primary constraint, substantial challenges remain regarding infrastructure availability and the integration of storage with charging stations. This paper seeks to offer a comprehensive perspective on the design and deployment of smart, scalable, and energy-efficient charging systems, with particular emphasis on cascaded and bidirectional topologies, as well as hybrid storage solutions, which represent promising pathways for the advancement of future EV charging infrastructure. Full article

Ferroelectric materials have attracted great attention for photocatalytic hydrogen (H₂) evolution due to their internal depolarization fields that promote carrier separation and directional migration. However, conventional inorganic ferroelectrics often suffer from wide band gaps and low conductivity, limiting their solar-to-hydrogen conversion efficiency. Here, we report a two-dimensional (2D) multilayered perovskite ferroelectric, [butylammonium]₂[ethylammonium]₂Pb₃I₁₀ (BAPI), which integrates robust spontaneous polarization (P_s) and excellent semiconductor properties to enable efficient photocatalysis. Under simultaneous light and ultrasonic excitation, BAPI/Pt (1 wt%) achieves a H₂ evolution rate of 1256 μmol g⁻¹ h⁻¹, which is twice that under light alone, due to dynamic polarization modulation that mitigates ionic screening and enhances internal electric fields. Notably, this enhancement vanishes when BAPI transitions to a centrosymmetric, nonpolar phase at 323 K, confirming the critical role of P_s. These findings offer a new pathway toward high-performance ferroelectric photocatalysts for solar hydrogen production. Full article

A novel all-sp³-hybridized superhard carbon allotrope, Ibca-C₆₄, is proposed based on first-principles calculations combined with the RG² (space group and graph theory) structure search method. A systematic investigation of its stability, mechanical properties, and electronic structure is performed. The results indicate that the energy difference between Ibca-C₆₄ and diamond is only 0.295 eV/atom, suggesting its metastability. Detailed analysis of its elastic constants and phonon spectrum confirms both mechanical and dynamical stability. The Ibca-C₆₄ structure demonstrates exceptional mechanical performance, with a Vickers hardness of 83.9 GPa. Furthermore, it possesses a wide direct band gap of 5.58 eV, indicating that Ibca-C₆₄ is a superhard semiconductor material with outstanding mechanical properties. Full article

Intermediate-band photovoltaics promise single-junction efficiencies that exceed the Shockley and Queisser limit, yet viable material platforms and device geometries remain under debate. Here, we perform comprehensive two-dimensional device-scale simulations using Silvaco Atlas TCAD to analyze p-i-n In_0.20Ga_0.80N solar cells in which the intermediate band is supplied by In_0.35Ga_0.65N quantum dots located inside the intrinsic layer. Quantum-dot diameters from 1 nm to 10 nm and areal densities up to 116 dots per period are evaluated under AM 1.5G, one-sun illumination at 300 K. The baseline pn junction achieves a simulated power-conversion efficiency of 33.9%. The incorporation of a single 1 nm quantum-dot layer dramatically increases efficiency to 48.1%, driven by a 35% enhancement in short-circuit current density while maintaining open-circuit voltage stability. Further increases in dot density continue to boost current but with diminishing benefit; the highest efficiency recorded, 49.4% at 116 dots, is only 1.4 percentage points above the 40-dot configuration. The improvements originate from two-step sub-band-gap absorption mediated by the quantum dots and from enhanced carrier collection in a widened depletion region. These results define a practical design window centred on approximately 1 nm dots and about 40 dots per period, balancing substantial efficiency gains with manageable structural complexity and providing concrete targets for epitaxial implementation. Full article

Titanium dioxide (TiO₂) is a benchmark photocatalyst for environmental applications, but its limited visible-light activity due to a wide band gap and fast charge recombination restricts its practical efficiency. This study presents the development of heterostructured Ag (Au)/MoS₂-TiO₂ inverse opal (IO) films that synergistically integrate photonic, plasmonic, and semiconducting functionalities to overcome these limitations. The materials were synthesized via a one-step evaporation-induced co-assembly approach, embedding MoS₂ nanosheets and plasmonic nanoparticles (Ag or Au) within a nanocrystalline TiO₂ photonic framework. The inverse opal architecture enhances light harvesting through slow-photon effects, while MoS₂ and plasmonic nanoparticles improve visible-light absorption and charge separation. By tuning the template sphere size, the photonic band gap was aligned with the TiO₂-MoS₂ absorption edge and the localized surface plasmon resonance of Ag, enabling optimal spectral overlap. The corresponding Ag/MoS₂-TiO₂ photonic films exhibited superior photocatalytic and photoelectrocatalytic degradation of tetracycline under visible light. Ultraviolet photoelectron spectroscopy and Mott–Schottky analysis confirmed favorable band alignment and Fermi level shifts that facilitate interfacial charge transfer. These results highlight the potential of integrated photonic–plasmonic-semiconductor architectures for efficient solar-driven water treatment. Full article

Tantalum oxide is a wide bandgap material commonly used as an insulating dielectric layer for devices. In this work, hexagonal Ta₂O₅ (δ-Ta₂O₅) films doped with tungsten (W) were deposited on α-Al₂O₃ (0001) by metal–organic chemical vapor deposition (MOCVD). The effects of W doping on the structural, morphology, and photoelectrical properties of the obtained films were studied. The results showed that all W-doped films were n-type semiconductors. The XRD measurement result exhibited that the increase in the W doping concentration leads to the changes in the preferred growth crystal plane of the films from δ-Ta₂O₅ ($10\overline{1}1$) to (0001). The 1.5% W-doped film possessed the best crystal quality and conductivity. The Hall measurement showed that the minimum resistivity of the film was 2.68 × 10⁴ Ω∙cm, and the maximum carrier concentration was 7.39 × 10¹⁴ cm³. With the increase in the W concentration, the surface roughness of the film increases, while the optical bandgap decreases. The optical band gap of the 1.5% W-doped film was 3.92 eV. The W doping mechanisms were discussed. Full article

The structural parameters and electronic structures of Sc- and Y-based nitride semiconductors that adopted hexagonal BN-like atomic sheets were investigated with calculations based on density functional theory (DFT). A hybrid exchange-correlation functional and spin–orbit coupling were employed for studies on the band structures. A strong variation in the band gap type, as well as the width, was revealed not only between the monolayer and bulk materials but also between the multilayer systems. An exceptionally wide range of band gaps from 1.39 (bulk) up to 3.59 eV (three layers) was obtained for two-dimensional materials based on ScN. This finding is related to two phenomena: significant contributions of subsurface ions into bands that formed a valence band maximum and pronounced shifts in conduction band positions with respect to the Fermi energy between the multilayer systems. The relatively low values of the work function (below 2.36 eV) predicted for the few-layer YN materials might be considered for applications in electron emission. In spite of the fact that the band gaps of two-dimensional materials predicted with hybrid DFT calculations may be overestimated to some extent, the electronic structure of homo- and heterostructures formed by rare earth nitride semiconductors seems to be an interesting subject for further experimental research. Full article

The generation of hot electrons through non-radiative decay processes of surface plasmons (SPs) has been extensively demonstrated, enabling the preparation of high-performance hot-electron photodetectors without limitations imposed by material band gap widths. In this paper, a near-infrared wideband hot-electron metal semiconductor photodetector (WHEMSPD) is proposed based on a metal grating plasmonic structure, and its optical and electrical properties are numerically verified. This structure exhibits excellent broadband characteristics within the long-wave near-infrared range (LW-NIR) of 1200–1800 nm, achieving an absorption of approximately 0.7 between 1200 and 1700 nm, with a peak of 0.98 at 1400 nm. The metal grating structure can effectively enhance the excitation of plasmons on the surface and thus increase the absorption within a larger bandwidth. In terms of electrical performance, the responsivity of the WHEMSPD reaches over 20 mA/W within the wavelength range of 1200–1500 nm, with the peak responsivity reaching 28.3 mA/W around 1320 nm. WHEMSPDs in the LW-NIR can be widely used in military, remote sensing, communication, and other related fields. Full article

This study employed first-principles density functional theory (DFT) to systematically investigate the influence of oxygen (–O) functional groups on the structural, magnetic, and electronic properties of Janus MXene CrScC. Nine distinct CrScCO₂ configurations with varying oxygen adsorption sites were examined. All configurations exhibited robust ferromagnetic ordering, with total magnetic moments ranging from 1 to 3 μ_B, predominantly contributed by Cr atoms. Notably, the majority of the configurations exhibited half-metallic behavior, characterized by fully spin-polarized conduction channels and half-metallic gaps spanning 0.23–1.54 eV, with one configuration approaching a spin-gapless semiconductor characterized by a minimal bandgap (<0.1 eV). The ground-state configuration demonstrated strong performance, featuring a 100% spin polarization ratio and a wide half-metallic gap of 0.44 eV, indicating significant potential for spintronic applications. Phonon spectrum calculations confirmed the dynamic stability of the half-metallic ground-state structure, while binding energy analysis highlighted the enhanced stability of the oxygen-functionalized system compared to pristine CrScC. These results demonstrate that –O functional groups play a key role in modulating the magnetism and electronic properties of CrScC, offering versatility for various spintronic device applications. Full article

Zinc oxide (ZnO), a cheap, abundant, biocompatible, and wide band gap semiconductor material with easy tunable morphologies and properties, makes it one of the mostly studied metal oxides in the area of materials science, physics, chemistry, biochemistry, and solid-state electronics. Its versatility, easy bandgap engineering with transitional and rare earth metals, as well as the diverse nanomorphology empower ZnO as a promising photocatalyst. The use of ZnO as a functional material is attracting increased attention both for academia and industry, especially under the current energy paradigm shift toward clean and renewable sources. Extensive work has been performed in recent years using ZnO as an active component for different photocatalytic applications. Therefore, a thorough and timely review of the process is necessary. The aim of this review is to provide a general summary of the current state of ZnO nanostructures, synthesis strategies, and modification approaches, with the main application focus on varied photocatalysis applications, serving as an introduction, a reference, and an inspiration for future research. Full article

Using the Bridgman technique, GaSe single crystals were obtained which were mechanically split into plane-parallel plates with a wide range of thicknesses. By heat treatment in air at 820 °C and 900 °C, for 30 min and 6 h, micro- and nanocomposite layers of Ga₂Se₃–Ga₂O₃ and β–Ga₂O₃ (native oxide) with surfaces made of nanowires/nanoribbons were obtained. The obtained composite Ga₂Se₃–Ga₂O₃ and nanostructured β–Ga₂O₃ are semiconductor materials with band gaps of 2.21 eV and 4.60 eV (gallium oxide) and photosensitivity bands in the green–red and ultraviolet-C regions that peaked at 590 nm and 262 nm. For an applied voltage of 50 V, the dark current in the photodetector based on the nanostructured β–Ga₂O₃ layer was of 8.0 × 10⁻¹³ A and increased to 9.5 × 10⁻⁸ A upon 200 s excitation with 254 nm-wavelength radiation with a power density of 15 mW/cm². The increase and decrease in the photocurrent are described by an exponential function with time constants of τ_1r = 0.92 s, τ_2r = 14.0 s, τ_1d = 2.18 s, τ_2d = 24 s, τ_1r = 0.88 s, τ_2r = 12.2 s, τ_1d = 1.69 s, and τ_2d = 16.3 s, respectively, for the photodetector based on the Ga₂Se₃–Ga₂S₃–GaSe composite. Photoresistors based on the obtained Ga₂Se₃–Ga₂O₃ composite and nanostructured β–Ga₂O₃ layers show photosensitivity bands in the spectral range of electronic absorption bands of ozone in the same green–red and ultraviolet-C regions, and can serve as ozone sensors (detectors). Full article

The precise fabrication of semiconductor-based photonic crystals with tailored optical properties is critical for advancing photonic devices. GaP(111) is a material of particular interest due to its high refractive index, wide optical bandgap, and pronounced optical anisotropy, offering unique opportunities for photonic applications. Its near-lattice matching with silicon substrates further facilitates integration with existing silicon-based technologies. In this study, we present the growth of high-quality GaP(111) thin films using gas-source molecular-beam epitaxy (GSMBE), achieving atomically smooth terraces for the homo-epitaxy of GaP(111). We demonstrate the fabrication of photonic crystal cavities from GaP(111), employing AlGaP(111) as a sacrificial layer, and achieve a quality factor of 1200 for the cavity mode with resonance around 1500 nm. This work highlights the potential of GaP(111) for advanced photonic architectures, particularly in applications requiring strong light confinement and nonlinear optical processes, such as second-harmonic and sum-frequency generation. Full article

Diamond is a semiconductor with a large band gap (5.48 eV), high carrier mobility (the highest for holes), high electrical resistance and low capacitance. Thanks to its outstanding properties, diamond-based detectors offer several advantages, among others: high signal-to-noise ratio, fast response, intrinsic pulse-shape discrimination capabilities for distinguishing different types of radiation, as well as operation in pulse and current modes. The mentioned properties meet most of the demanding requests that a radiation detection material must fulfil. Diamond detectors are suited for detecting almost all types of ionizing radiation including X-ray and UV photons, resulting also in blindness to visible photons and are used in a wide range of applications including ones requiring the capability to withstand harsh environments. After reviewing the fundamental physical properties of synthetic single crystal diamond (SCD) grown by microwave plasma enhanced chemical vapor deposition (MWPECVD) technique and the basic principles of diamond-photon interactions and detection, the paper focuses on SCD detectors developed for X-ray and UV detection, discussing their configurations, construction techniques, advantages, and drawbacks. Applications ranging from X-ray detection around accelerators to UV detection for fusion plasmas are addressed, and future trends are highlighted too. Full article

Obtaining wide energy-gap semiconductor ultra-thin films is an important aspect for their application in sulfide-based solar cells. By reducing the optical losses associated with light reflection and exhibiting absorption edge shifts towards short wavelengths, these layers can optimize the amount of photons interacting with the active photovoltaic material, which increases the conversion efficiency of the solar cell. Ultra-thin CdS films were prepared by a low-cost chemical synthesis and the impact of silver doping on the optical, structural, and morphological properties was evaluated. SEM micrographs revealed that the layers are ultra-thin, homogeneous and uniform, with a reduction in particle size with increasing doping concentration. X-ray diffraction data confirmed the crystallization of CdS in the hexagonal phase for all prepared samples. A low concentration contributed to the formation of Ag₂S in the monoclinic phase according to the diffractograms. The optical properties of the thin films revealed an absorption edge shift that increased the CdS band gap from 2.267 ± 0.007 to 2.353 ± 0.005 eV with increasing doping concentration, improving the spectral transmittance response. These results make these layers particularly useful for implementation in next-generation flexible photovoltaic devices. Full article

Due to a lower InN bandgap $\mathrm{e}\mathrm{n}\mathrm{e}\mathrm{r}\mathrm{g}\mathrm{y} {\mathrm{E}}_{\mathrm{g}}~0.7 \mathrm{e}\mathrm{V}$, ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}/\mathrm{S}\mathrm{a}\mathrm{p}\mathrm{p}\mathrm{h}\mathrm{i}\mathrm{r}\mathrm{e}$ epifilms are considered valuable in the development of low-dimensional heterostructure-based photonic devices. Adjusting the composition x and thickness d in epitaxially grown films has offered many possibilities of light emission across a wide spectral range, from ultraviolet through visible into near-infrared regions. Optical properties have played important roles in making semiconductor materials useful in electro-optic applications. Despite the efforts to grow ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}$/Sapphire samples, no x- and d-dependent optical studies exist for ultrathin films. Many researchers have used computationally intensive methods to study the electronic band structures ${\mathrm{E}}_{\mathrm{j}}\left(\overrightarrow{\mathrm{k}}\right),$ and subsequently derive optical properties. By including inter-band transitions at critical points from ${\mathrm{E}}_{\mathrm{j}}\left(\overrightarrow{\mathrm{k}}\right)$, we have developed a semiempirical approach to comprehend the optical characteristics of InN, GaN and ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}$. Refractive indices of ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}$ and sapphire substrate are meticulously integrated into a transfer matrix method to simulate d- and x-dependent reflectivity $\mathrm{R}\left(\mathrm{E}\right)$ and transmission $\mathrm{T}\left(\mathrm{E}\right)$ spectra of nanostructured ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}/\mathrm{S}\mathrm{a}\mathrm{p}\mathrm{p}\mathrm{h}\mathrm{i}\mathrm{r}\mathrm{e}$ epifilms. Analyses of $\mathrm{R}\left(\mathrm{E}\right)$ and $\mathrm{T}\left(\mathrm{E}\right)$ have offered accurate x-dependent shifts of energy gaps for ${\mathrm{I}\mathrm{n}}_{\mathrm{x}}{\mathrm{G}\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}$ (x = 0.5, 0.7) in excellent agreement with the experimental data. Full article