Journal of Materials Science: Materials in Electronics最新文献

Silver-doped CdTe quantum dots (Ag:CdTe QDs) and their core/shell derivatives with thin CdS and ZnS layers (Ag:CdTe/X, X = CdS or ZnS) were synthesized via a colloidal route and systematically characterized. X-ray diffraction confirmed a cubic zinc-blende phase for all samples. Ag incorporation altered CdTe growth from octahedral to cubic by suppressing the (111) orientation and enhancing the (200) facet, slightly reducing crystallinity. CdS shell deposition partially restored the (111) orientation, while ZnS shells further recovered structural features resembling pristine CdTe QDs. High-resolution TEM revealed ~ 3.7 nm Ag:CdTe cores with ~ 0.7–1.4 nm shell thicknesses. Optical measurements showed redshifts in absorption (650–750 nm) and emission (538–604 nm), with a bandgap reduction from 2.11 to 1.83 eV. Photovoltaic studies demonstrated that Ag-doping increased the power conversion efficiency (PCE) ~ 64% via enhanced band-edge absorption and acceptor-like states promoting charge separation. CdS and ZnS shells further enhanced PCEs to 3.27% (~ 179% increase) and 2.96% (~ 153% increase), enabled by quasi-Type-II and Type-I band alignments, respectively. These results highlight the synergistic impact of Ag-doping and core/shell engineering in improving QDSSC performance and emphasize the need for further optimization of shell thickness, surface passivation, and device architecture to achieve higher efficiencies.

Since dyeing wastewaters cause serious environmental problems effecting human health, it must be treated before being discharge into the environment. In this work, Mg–Ni–Y–La alloy with the nominal compositions of Mg₆₅Ni₁₈Y₁₅La₂ was successfully synthesized by mechanical alloying (MA) method. The microstructural properties, morphological evaluation and thermal behavior of the powders at the different stages of milling time, were examined by the combination of X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) and the crystallite sizes of the powders were estimated by the broadening of XRD peaks according to the Debye Scherrer formula. The XRD results showed that Ni₃Y, La₂Mg₁₇, and Mg₂Ni phases were formed with the average crystallite size of 9.3 nm after 100 h milling time. The exothermic peak at about 487 °C in the DSC curve of 5 h milled powders was observed. The obtained Mg₆₅Ni₁₈Y₁₅La₂ alloy was used as a photocatalyst in the color and chemical oxygen demand (COD) removal from the simulated wastewater containing 50 mg l⁻¹ Methyl Orange. In order to improve the applicability in wastewater treatment system, the decolorization efficiencies of the dyeing solution consisting of Methyl Orange, Rhodamine B, and Methylene Blue dyes were also examined using by the same experimental methods and materials. The Mg₆₅Ni₁₈Y₁₅La₂ alloy powders showed the highest catalytic activity with its ability by 92% color and 98% COD removal efficiencies within 3 min in wastewater containing 50 mg l⁻¹ Methyl Orange. In addition, 92, 79, and 77% removal efficiencies were achieved for Methyl Orange, Rhodamine B, and Methylene Blue, respectively. The Mg₆₅Ni₁₈Y₁₅La₂ alloy is remarkable for demonstrating the capability of simultaneously degradation of anionic and cationic dyes. Thus, the ability of Mg₆₅Ni₁₈Y₁₅La₂ alloy to treat simulated textile wastewater samples and simultaneously remove of dyes was successfully investigated and it provided insight into overcoming the limitations of existing photocatalysts in simultaneous dye degradation and real wastewater treatment. So it is valuable and promising for the treatment of wastewaters generated by textile dyeing manufacturing in future.

This research explores supercapacitors made from activated carbon (AC) from areca nuts, Nickel oxide (NiO), and Silver phosphate (Ag₃PO₄). The study investigates the synthesis, characterization, and electrochemical performance of composite materials. The morphology, structural properties, and surface characteristics of the composite materials were verified by methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), and surface area analysis. Electrochemical evaluations, including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge–discharge (GCD), were conducted to assess the capacitive performance along with its antimicrobial properties. The results indicated that the NiO/AC/Ag₃PO₄ composite exhibited significantly improved specific capacitance, energy density, and cycling stability compared to activated carbon alone. The synergistic effects of NiO and Ag₃PO₄ contributed to enhanced charge storage capability and faster ion transport. The optimized composite demonstrated a specific capacitance of 579 F/g at a current density of 1 A/g. These results show that the NiO/AC/Ag₃PO₄ improves the for supercapacitor application.

This study investigates the electrical performance of Schottky barrier diodes (SBDs) using a polyvinyl pyrrolidone (PVP) interlayer doped with microwave-synthesized Gd₂O₃ nanostructures. Structural and optical properties of Gd₂O₃ were characterized by XRD, UV–Vis, FE-SEM, and EDX analyses. Electrical parameters, including barrier height, ideality factor, leakage current, and resistance values, were extracted using thermionic emission theory, Cheung’s method, and the modified Norde function. The incorporation of the PVP:Gd₂O₃ interfacial layer increased the zero-bias barrier height from 0.575 eV to 0.782 eV, enhanced the rectification ratio from 21 to 1440, and reduced the reverse leakage current by nearly four orders of magnitude compared to the conventional Au/n-Si SBD. Additionally, the ideality factor decreased from 6.86 to approximately 5.2, indicating improved interface quality. These results demonstrate that the PVP:Gd₂O₃ nanocomposite is an effective interlayer material for improving the performance of SBDs in nano-electronic and optoelectronic applications.

This study presents the fabrication and characterization of a silicon-based heterojunction photodiode featuring a rare-earth orthoborate interlayer, aimed at enhancing high-sensitivity photodetection. The orthoborate compound was synthesized by the solid-state reaction method and confirmed to have high phase purity and thermal stability up to 800  C. Structural and spectroscopic analyses (PXRD, FTIR, and SEM/EDS) verified a uniform microstructure and well-defined borate framework. The device showed clear rectifying behavior with very low dark current, indicating good junction quality and effective carrier separation. Illumination induced systematic changes in ideality factor, barrier height, and saturation current, consistent with photon-assisted transport. The photodiode achieved high photosensitivity and stable responsivity across different illumination levels, particularly under low-light conditions. Under 100 (mW,cm^{ - 1}) illumination, the responsivity reached (0.43{ }A/W) and specific detectivity exceeded (2.5{ } times 10^{10} {text{ Jones}}). Time-resolved measurements demonstrated rapid and repeatable switching with no hysteresis, confirming operational stability. These results demonstrate that the (Al/NaSrLaleft( {BO_{3} } right)_{2} /n - Si) heterojunction is a promising platform for sensitive and stable photodetection in optoelectronic applications.

In this study, Ba₂SnO₄ nanostructures were successfully synthesized via the hydrothermal method and employed for gas sensing applications. Two samples were prepared with and without the use of a surfactant in order to investigate its influence on the structural, morphological, optical characteristics and gas sensing performance of Ba₂SnO₄ nanostructures. The obtained powders were processed into thick films using the screen-printing technique. Comprehensive characterization was carried out using X-ray diffraction (XRD), UV–Visible spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric /differential thermal analysis (TGA/DTA), Raman spectroscopy, and electrical measurements. The gas sensing performance of the synthesized Ba₂SnO₄ thick films was evaluated toward NO₂, NH₃, LPG, H₂S, ethanol, and methanol gases. Among them, NO₂ exhibited the highest response. Sample S1 showed a maximum sensitivity of 68.74% at 160 °C for 1000 ppm NO₂, whereas Sample S2 demonstrated enhanced performance with 82.13% sensitivity at a lower temperature of 120 °C and 600 ppm NO₂ concentration. The limits of detection (LOD) were determined to be 152.97 ppm for S1 and 705.72 ppm for S2, respectively. Both samples displayed fast response and recovery times, along with good selectivity, stability, and reusability, confirming the potential of Ba₂SnO₄ thick films particularly the CTAB-assisted sample as promising candidates for efficient NO₂ gas sensors.

Li₂Co_1.9Zn_0.1Mo₃O₁₂ microwave dielectric ceramics were synthesized via the solid-state reaction method and sintered at various temperatures to evaluate their structural evolution and dielectric performance. X-ray diffraction with Rietveld refinement confirmed a single-phase orthorhombic structure, with optimal densification (96.47% relative density) achieved at 775 °C. SEM, EDS, and Raman analyses validated microstructural evolution, elemental distribution and vibration characteristics. Zn²⁺ substitution modified the sintering behavior, enabled effective densification at a comparatively low temperature of 775 °C. Under these conditions, the ceramics exhibited a dielectric constant (ε_r) of 10.10, a quality factor (Q × f) of 13,800 GHz, and a temperature coefficient of resonant frequency (τ_f) of − 45.96 ppm/°C. The inverse correlation between τ_f and octahedral distortion was established, highlighting the role of lattice symmetry in thermal stability.

The growing demand for high-frequency electronic components has intensified the search for dielectric materials with improved polarization and conduction behavior. Although, Magnesium aluminate (MgAl₂O₄) spinels offer excellent thermal and mechanical stability, their limited dielectric response restricts wider technological use. This study investigates whether iron substitution can effectively enhance the structural and dielectric characteristics of MgAl₂O₄, addressing the need for tunable materials suitable for advanced electronic applications. A series of iron-doped compositions with the general formula MgAl_2−xFe_xO₄ (x = 0.0, 0.1, 0.15, 0.2, and 0.25) were prepared using an economical citrate sol–gel method. The formation of the spinel phase was confirmed through X-ray diffraction. FTIR spectroscopy revealed characteristic AlO₆ vibrational bands near 500 and 700 cm^-1. Dielectric analysis showed a progressive increase in dielectric constant (from 4 × 10² to 9 × 10²), dielectric loss (from 6.5  ×  10² to 1.6  ×  10³), and tangent loss (from 1.2 to 1.5) with increasing iron content. Impedance and Cole–Cole analyses further demonstrated reduced resistance and improved relaxation dynamics in Fe-substituted samples. The findings establish iron doping as an effective strategy for tailoring the dielectric behavior of MgAl₂O₄, underscoring its potential for high-frequency electronics, sensors, and energy-related devices.

In this current study, the Zr-CdFe₂O₄ nanoparticle (ZCDF NPs) was fabricated by a facile green-mediated (Tulasi extract) combustion method. Their structural properties were well probed through various spectral studies such as Powder-X-ray diffraction (PXRD), Scanning Electron Microscopy- Energy Dispersive X-ray (SEM-EDAX), Fourier Transform Infrared Spectroscopy (FT-IR), and UV–Visible spectroscopy. The XRD results possess a more optimistic with controlled particle size (29 ± 0.5 nm) and crystalline nature of ZCDF NPs. The change in electronic characteristics of CDF NPs by the impact of Zr dopant was recorded by UV–Visible absorption spectroscopy. The lower energy band gap (3.41 eV) of ZCDF NPs associated to trapping electrons-holes and its enhanced dye degradation activity measured using Kubelka–Munk relation. The Ec_B & Ev_B edge potentials of ZCDF NPs were measured to be -3.93 and -1.73 eV, respectively, using observed of electronegativity of ZCDF NPs of 1.67 eV. An excellent photocatalytic performance on Rose Bengal (RB) dye under Sun-light irradiation was observed to be 87.5% at 60 min and its kinetic rate of 34.22 × 10^–3 min⁻¹. The consequence of Zr ions over their electrochemical properties were effectively studied by CV, EIS and GCD electrochemical techniques in 0.1 M KCl using 3-electrode system. The measured specific capacitance of modified carbon-ZCDF electrode was reported to be 186 F/g at current density (1 A/g) using GCD plots. An excellent electrochemical sensing analysis of prepared carbon-ZCDF NPs paste electrode on Lead (Pb²⁺) metal ions at different concentrations of 1–5 μM evidenced by existence of additional peak at—0.93 V potential in CV plot measured between the potential window from + 0.6 to -1.2 V. This experimental measurements finds an effective and promising new route for electrochemical detection of various heavy metal substance in electrolyte.

Materials must achieve an ideal balance between low surface reflection and high internal dissipation in electromagnetic wave (EMW) absorption. CuSe shows great potential in EMW absorption due to its excellent electrical conductivity and optical absorption properties, but it suffers from impedance mismatch caused by an excessively high real part of dielectric constant (ε′), leading to strong surface reflection and limiting both the effective absorption bandwidth and matching thickness. Cu-MOF with a low ε′ (~ 4.4) and porous structure was introduced as a “dielectric buffer layer”. The EMW performance of the CuSe/Cu-MOF laminate, combining the high-loss characteristics of CuSe with the buffering effect of Cu-MOF, can be significantly improved. Therefore, gradient heterostructures of CuSe/Cu-MOF laminates are fabricated in situ via a two-step hydrothermal route, and 500 nm hexagonal CuSe nanosheets (conductive islands) are dispersed within a 3D porous matrix of 20 µm octahedral Cu-MOF (insulating seas). A minimum reflection loss of –41 dB was recorded at 10.4 GHz with 3.5 mm thickness and a CuSe content of 25 wt% (75 wt% Cu-MOF), and an effective absorption bandwidth (RL ≤ –10 dB) extended from 8.2 to 11.2 GHz, which exhibits a reduced ε′ of 9 and a corresponding increase in normalized input impedance (|Zin/Z₀|) to approximately 0.9, indicating significantly improved impedance matching. Meanwhile, interfacial polarization and multiple-scattering mechanisms are synergistically enhanced, effectively prolonging the EMW attenuation path. This method yields gram-scale batches with < 2 g·cm⁻³ density and broad effective bandwidth at a few-millimetre thickness, offering a potentially scalable route toward lightweight microwave absorbers.