Journal of Electronic Materials最新文献

A series of amorphous Fe_73.5Cu₁Nb₃Si_17.5−xAl_xB₅ (x = 0.2, 0.4, 0.6) alloys were prepared via single-roller melt spinning technology, and their crystallization processes were systematically analyzed. Differential scanning calorimetry results reveal that the onset temperature of primary crystallization, corresponding to the precipitation of the soft magnetic crystalline phase, decreases with increasing Al content, whereas the secondary crystallization onset temperature, associated with the precipitation of the hard magnetic crystalline phase, increases. The addition of Al broadens the temperature range suitable for forming dual-phase nanocrystalline soft magnetic alloys. Analysis of Kissinger plots indicates that the energy barrier required for nucleation in amorphous alloys gradually decreases with Al doping, enabling crystallization to occur at lower temperatures. The sample with x = 0.6 has the highest saturation magnetization and magnetic permeability due to its larger crystalline phase volume fraction.

In this study, cobalt-doped manganese ferrite particles (Mn_1−xCo_xFe₂O₄; x = 0.0, 0.03, 0.06, 0.09) were synthesized via the sol–gel method to explore their potential for energy storage applications. The effects of cobalt content on the structural, morphological, and dielectric properties were examined. X-ray diffraction (XRD) confirmed a single-phase cubic spinel structure (Fd-3 m) without secondary phases. Higher Co content led to reduced crystallite size due to strain from ionic size mismatch. Fourier transform infrared (FTIR) spectroscopy showed characteristic spinel ferrite vibrations. Scanning electron microscopy (SEM) revealed nearly spherical to irregularly rounded grains with moderate agglomeration, and energy-dispersive x-ray spectroscopy (EDX) verified cobalt incorporation and elemental uniformity. The dielectric properties were investigated at room temperature using an LCR meter, focusing on capacitance, dielectric constants (({varepsilon }_{r}{prime}), ({varepsilon }_{r}^{{prime}{prime}})), tangent loss (tan δ), and ac conductivity (σ_ac). Dielectric analysis based on Maxwell–Wagner and Koop’s theory showed that cobalt doping improved both dielectric behavior and conductivity, with x = 0.09 achieving the best performance, highlighting the energy storage potential of Mn_1−xCo_xFe₂O₄.

The simultaneous demand for clean energy and water purification drives the development of multifunctional photocatalysts and electrocatalysts. We sought to fabricate a Cu_0.5 Zn_0.5 Fe₂O₄–graphitic carbon nitride hybrid using ultrasonic-assisted hydrothermal processing and assess its efficacy for sun-driven degradation of rhodamine B and as counter electrodes in dye-sensitized solar cells (DSSCs). X-ray Diffraction (XRD) validates the formation of pure spinel Cu_0.5 Zn_0.5 Fe₂O₄ phase and the presence of g-C₃N₄. X-ray photoelectron spectroscopy (XPS) study demonstrates the interfacial electronic interaction. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) results demonstrate that Cu_0.5 Zn_0.5 Fe₂O₄ nanoparticles are uniformly affixed to g-C₃N₄ sheets. Brunauer–Emmett–Teller (BET) analysis indicates a mesoporous structure with a surface area of 33.7 m² g^–1. UV–Vis diffuse reflectance spectroscopy (DRS) results yield a refined E_g of 2.20 eV and photoluminescence (PL) quenching signifies effective charge separation. Under natural sunlight, the optimized Cu_0.5 Zn_0.5 Fe₂O₄–g-C₃N₄(25%) degrades 94.6% of RhB in 90 min. The dye-sensitized solar cell (DSSC) counter electrode has a power conversion efficiency of 6.14% (J_sc = 15.06 mA cm⁻², V_oc = 0.75 V, FF = 0.64), with a charge transfer resistance (R_ct) of 6.25 Ω, a high saturation current density (J₀) of 0.92 mA cm^–2, and almost 95% power conversion efficiency (PCE) retention after 15 days. This study presents, for the first time, a CZFO–g-C₃N₄ heterojunction that concurrently serves as a visible-light photocatalyst and a platinum-free counter electrode for dye-sensitized solar cells, providing a sustainable approach that integrates pollutant degradation with solar energy conversion.

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Owing to the natural abundance of sodium, sodium-ion batteries (SIBs) serve as a more cost-effective option compared with lithium-ion batteries (LIBs), while offering comparable energy storage capabilities. This study presents the compositional optimizations, structural characterizations, and electrochemical performance of a new mixed sodium (Na) superionic conductor (NASICON)-type polyanionic material, NaFe₂PO₄(SO₄)₂ (NFPS). Subsequently, the introduction of Ni²⁺ doping serves to simultaneously improve the structural integrity and electronic conductivity of the material, leading to a collective enhancement of the sodium-ion diffusion channels. The Ni²⁺-incorporated phase, NaFe_1.92Ni_0.08PO₄(SO₄)₂, exhibits faster Na⁺ diffusion, resulting in superior rate and cycling performance versus NFPS. After 80 cycles at 25 mA g⁻¹, NFPS-Ni_0.08 maintains a discharge capacity of 58.7 mA h g⁻¹, outperforming undoped NFPS by 20%.

In this paper, a comparative investigation of different intriguing physical parameters (i.e. eigenfrequencies, susceptance, participation factor, and energy dynamics), for piezoceramics and piezopolymer composites are investigated in order to balance energy harvesting capability with enhanced sensing efficiencies. As a proof of concept, piezoceramics including lead-zirconate-titanate family (PZT4, PZT5A, and PZT8), barium titanate (BaTiO₃), aluminum nitride (AIN), NEPEC6, lithium niobate (LiNbO₃), and piezopolymers including polyvinylidene-fluoride (PVDF), polyvinylidene-fluoride-trifluoro-ethylene (PVDF-TrFE), and nylon 11 are selected for investigation. Simulation results confirmed that among the lead-zirconate-titanate family, PZT8 offers extremely high mechanical stiffness even at elevated eigenfrequencies (~141.32 KHz), which makes it suitable for high-frequency actuation applications. In contrast, PZT4 and PZT5A reveal significant susceptance peaks around 40 KHz and 90–100 KHz eigenfrequencies and substantial variation in susceptance (0.0031–0.0040 S (),), thereby indicating enhanced sensing properties. On the contrary, BaTiO₃, NEPEC6, and LiNbO₃ offer relatively lower sensitivity owing to insignificant susceptance fluctuation in different eigenfrequencies. A comparative study shows that NEPEC6 is more energy efficient compared with polymers PVDF. Among the piezoceramics family, PZT5A demonstrates the most significant displacement along the z-axis, whereas PZT4 and PZT8 exhibit a higher effective modal mass, hence lower energy efficiency. Moreover, it is observed that soft materials including nylon 11 exhibit lower energy conversion efficiency, whereas, rigid materials (e.g. BaTiO₃, NEPEC6) are capable of storing and releasing greater amounts of energy.

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Industrial waste diesel distillate is a by-product rich in polycyclic aromatic hydrocarbons (PAHs). To address the valorization and environmental challenges associated with the industrial waste diesel distillate, this study aims to transform this low-value waste into high-performance materials. It reports a low-cost, low-temperature (750°C) catalytic method to synthesize graphene from waste diesel distillate using melamine sponge scaffolds impregnated with nickel hydroxide. When used as a supercapacitor electrode, the obtained material demonstrated excellent rate capability (55.63% retention) and outstanding cycling stability, retaining 78.9% of its capacitance after 10,000 cycles. This performance vastly surpasses the control (carbonized sponge without catalyst and diesel distillate, 19.98% retention), highlighting an efficient “waste-to-wealth” strategy for producing advanced and sustainable energy storage materials with significant environmental and economic benefits.

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The graphene preparation process from diesel distillate, material characterization and Schematic structure of graphene supercapacitor, with long cycle performance.

To develop novel materials for improving the performance of organic solar cells (OSC), 17 molecules were designed as donor materials for OSC. These molecules employed triphenylamine as a donor unit, quinoxaline, 2–(thiophen–2–yl) quinoxaline, 2,3–bis(2–thienyl) quinoxaline, thieno[3,4–b] pyrazine, and thieno[3,4–b] quinoxaline as acceptor units, and benzene or thiophene as π-conjugated bridges. These 17 molecules were connected through three patterns: D–A–D, D–π–A–D, and D–π–A–π–D. Firstly, the optical and electronic properties of these donor materials at gas-phase ground state were calculated using the density functional theory. The highest occupied molecular orbital (HOMO) energies, energy gaps, and dipole moments were determined. The results showed that the HOMO energies of the designed molecules (S1–S17) ranged from –4.3 to –4.7 eV, the energy gaps ranged from 1.4 to 2.9 eV, and the dipole moments ranged from 0 Debye to 1.7 Debye. Molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene serving as the π-bridge exhibited larger energy gaps than those linked by the D–A–D pattern. When thiophene was used as the π-bridge, the opposite conclusion was obtained. Among these donor materials, S15–S17 with AM5 (thieno[3, 4–b]quinoxaline) as an acceptor unit demonstrated the smallest energy gaps, which favored electron transfer between donor and acceptor units. The Scharber model was utilized to predict photoelectric conversion efficiency (PCE) of these molecules, and it was found that the OSC with S15/PC₆₁BM and S16/PC₆₁BM as the active layer can achieve a PCE of 8% and 10%, respectively. Secondly, time-dependent density functional theory was employed to calculate the UV–Vis absorption spectra of these 17 donor materials. S15 and S16 with AM5 as an acceptor unit had the widest absorption spectral range. The UV–Vis absorption spectra of molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene as the π–bridge exhibited blue shifts compared with those linked by D–A–D. The spectra showed red shifts and broader absorption ranges for D–π–A–D and D–π–A–π–D patterns compared with D–A–D when thiophene was the π–bridge. Finally, the ground-state and excited-state properties of these 17 donor materials were calculated in chloroform. The results showed that the dipole moments of all 17 molecules increased significantly, and their UV–Vis absorption spectra exhibited red shifts compared with gas-phase conditions.

In this work, the influence of graphene nanoplatelets (GNPs) was investigated with respect the structural, optical, electrical, dielectric, and magnetic properties of Ni_0.5Co_0.5Se_0.09Fe_1.88O₄/x-GNPs (NCSF/x-GNPs, 0–5 wt.% with a step size of 1.25) synthesized via the sol–gel auto-combustion route. X-ray diffraction (XRD) analysis confirmed the cubic spinel structure of all samples, with a minimum crystallite size of 18.16 nm. Scanning electron microscopy (SEM) micrographs revealed that GNPs were uniformly coated with NCSF nanoparticles, exhibiting slight aggregation and clustering. UV–Vis data showed that the sample with 0 wt.% GNPs had the lowest optical bandgap of 2.09 eV. Current–voltage (I–V) measurements verified the semiconducting behavior of the composites, with activation energies ranging from 0.16 eV to 0.59 eV. The minimum tangent loss, dielectric constant, and dielectric loss were recorded for the sample containing 3.75 wt.% GNPs, attributed to the conductive nature of GNPs and the hopping mechanism. Vibrating sample magnetometry (VSM) results indicated that saturation magnetization, remanence, and retentivity decreased up to 2.5 wt.% GNPs, then increased with further addition. The overall results suggest that NCSF/GNP composites possess promising potential for use as recoverable catalysts under visible light and in energy storage applications.

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The present work demonstrates the application of a Si/Perovskite heterojunction as a photodetector by varying the substrate as n-Si and p-Si for visible electromagnetic radiation. The deposition of a methylammonium lead bromide (MAPbBr₃) perovskite thin film was performed using the one-step spin coating method. The optimized heterojunction of p-Si/Perovskite thin film and n-Si/Perovskite thin film exhibited significant spectral responsivity and detectivity in no bias condition i.e., self-biased mode. The performance of the devices has been measured under different light intensities as well. The heterojunction parameters show promising applications in optoelectronic devices such as imaging, optical sensing, or communication devices.

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Accurate detection of uric acid (UA) is crucial due to its significant role in diagnosing and managing hyperuricemia, gout, and other metabolic disorders, thereby necessitating reliable and efficient analytical methods. In this study, a novel hybrid electrode composed of polythiophene (PT)-incorporated cobalt hexacyanoferrate (Co-PB) was developed via a facile in situ oxidative polymerization approach. Comprehensive characterizations, including x-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller (BET) analyses, confirmed the successful hybridization and enhanced surface properties. The XRD results verified the preservation of the Co-PB crystalline phase, accompanied by a reduction in crystallite size from 64 nm to 41 nm upon PT incorporation. Morphological analysis revealed a uniform distribution of Co-PB nanocubes within the PT matrix, forming a core–shell architecture. N₂ adsorption–desorption studies indicated an increase in surface area from 112.3 m² g⁻¹ (Co-PB) to 146.7 m² g⁻¹ (PT/Co-PB). The PT/Co-PB-modified electrode exhibited excellent electrochemical performance, with differential pulse voltammetry showing a wide linear detection range of 0.1–1000 µM and a low limit of detection of 0.159 µM. The sensor demonstrated outstanding selectivity toward UA against common interferents and maintained 94% of its initial response after 14 days, reflecting high stability. Moreover, real sample analysis showed reliable performance, achieving recovery rates between 96.8% and 103.2% in spiked human urine samples. These findings highlight the PT/Co-PB hybrid as a low-cost, scalable, and ultrasensitive electrochemical platform for efficient clinical monitoring of uric acid.

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