Journal of Materials Science: Materials in Electronics最新文献

Zn-doped CuFe₂O₄ spinel ferrites are synthesized via a sol–gel route, and the influence of Zn incorporation on their structural, optical, and magnetic properties was systematically investigated. X-ray diffraction and FTIR analyses confirm a progressive transformation of CuFe₂O₄ from a tetragonal to a cubic spinel phase with increasing Zn content. Optical characterization using UV–vis spectroscopy shows that the band gap varies from 1.71 to 1.23 eV, reflecting the effects of lattice distortion and cation redistribution. Magnetic measurements reveal a gradual transition from hard to soft magnetic behavior, characterized by a pronounced decrease in coercivity and a simultaneous enhancement in saturation magnetization. These findings indicate that Zn substitution effectively modulates exchange interactions and local magnetic moments, offering valuable insights into the design of ferrite materials for optoelectronic and magnetic applications.

This study presents transparent, flexible, lead-free polyvinyl butyral (PVB) films that utilize FeWO₄ nanoparticles to substantially enhance gamma-photon attenuation properties and thermal stability, thereby facilitating the development of lightweight shielding materials. Herein, PVB films doped with FeWO₄ (0%, 1%, 2%, and 3 wt.%) were synthesized via the solution casting technique. XRD demonstrated that FeWO₄ NPs possess a monoclinic primitive structure with a crystallite size of 47 nm. EDX and SEM were used to evaluate the morphology and elemental composition of the FeWO₄ NPs. Thermogravimetric analysis (TGA) revealed that incorporating FeWO₄ markedly improved the thermal stability of PVB films. The linear attenuation coefficient for gamma rays, ranging from 0.02 MeV to 15 MeV, was simulated using the MCNP6 code. The results indicate that the mass attenuation coefficient (MAC) rises progressively with increasing FeWO₄ content, particularly at low to intermediate gamma energies, accompanied by a decrease in both the half-value layer (HVL) and the mean free path (MFP) relative to pure PVB. MCNP6 simulation data align with the obtained Phy-X/PSD calculations and XCOM databases, indicating strong cross-validation among methods. The effective electron number, N_eff, increases with FeWO₄ content at photon energies where photoelectric and Compton processes dominate. The Fast neutron removal cross section (FNRCS) values of PVB/FeWO₄ nanocomposites increased by incorporating FeWO₄ NPs. PVB/FeWO₄ nanocomposites are proposed as an alternative to ecologically friendly and lead-free materials for radiation shielding.

The Cu-filled Through-Silicon Via (TSV) on the thermal–mechanical reliability of 3D-integrated circuit has become increasingly prominent. Conventional simulation methods typically treat Cu as the isotropic material and ignore the influence of Cu grains in the microstructure, leading to deviations between the simulation and experimented results. This paper proposes a thermal–mechanical-coupled analysis strategy based on the real TSV microstructure, and investigates the relationship between the TSV microstructure and its fatigue damage under thermal cycling loads. Firstly, the low-damage cross section of TSV, with roughness as low as 7.69 nm and band contrast of diffraction pattern as high as 164, was obtained by etching technique of focus ion beam. Then, the Response Surface methodology and Monte Carlo simulation were applied to optimize the key parameters of electron backscatter diffraction (EBSD), increasing the average band contrast of EBSD map from 89.33 to 98.11 and significantly improving the accuracy of microstructure characterization. Based on the high-quality EBSD data, the finite element model of TSV incorporating real grain numbers and orientations was constructed. Finally, through thermal cycling simulations, the effects of grain numbers and orientations on fatigue damage were investigated, which shows that the < 100 > orientation exhibits the best fatigue resistance. The real structure with random orientations is more prone to fatigue damage due to deformation incompatibility between grains. Furthermore, grain number is also closely related to fatigue damage, the higher the number of grains, the lower the risk of fatigue damage.

This study systematically investigated the optically stimulated luminescence (OSL) characteristics of heteroepitaxial diamond (HED) with two different nitrogen concentrations (3 ppb and 1 ppm). The nitrogen-rich sample exhibited substantially higher OSL intensity than the low-nitrogen sample, reflecting an increased density of trapping sites and luminescent centers associated with nitrogen-related defects. Both samples showed weak dose dependence below 10 Gy and saturation at 100–200 Gy, consistent with the classical center-depletion model. A pronounced enhancement in OSL sensitivity was observed only in the nitrogen-rich sample following pre-irradiation up to 400 Gy. This enhancement is attributed to increased trapped-electron population, activation of previously inactive luminescent centers, and improved radiative recombination efficiency. The enhancement was completely removed by annealing at 500 °C for 60 s, indicating that the effect originates from metastable changes in defect occupancy rather than permanent defect formation. The OSL emission spectra exhibited a single broad band between 500 and 800 nm, peaking at 620–650 nm, corresponding to the phonon sideband of NV⁻-related luminescence. No zero-phonon line at 637 nm was resolved, consistent with the broad-band, phonon-assisted nature of the measured OSL emission. The spectral shape remained unchanged after pre-irradiation. Fading measurements further revealed that the nitrogen-rich diamond possesses more thermally stable trap levels than the low-nitrogen sample. These findings demonstrate that nitrogen incorporation is an effective strategy for tuning the OSL performance of HED and the potential of nitrogen-rich HED for high-dose and reusable dosimetry applications.

High-quality methyl orange dye-doped adipic acid single crystals were harvested successfully at ambient temperature by solvent evaporation route. SXRD, PXRD, FT-IR and EDAX examination confirms the small appreciable amount of entry of dopant species in the grown crystalline matrix. Transmittance percentage of UV spectrum was suddenly dipped around 480–490 nm (n to π* transition peak) due to the occurrence of methyl orange dye absorption peak. Kurtz NLO experiment confirms decline in second harmonic generation efficiency value. The melting temperature is augmented in TG–DTA thermograms. Methyl orange dye MO-doped adipic acid crystals show potential for optoelectronic devices, acting as optical filters due to dipped transmission percentage and superior decomposition points, demonstrating increased thermal resilience for practical applications.

This article reports for first time, a comparative dielectric properties study of two dried flower biomasses (Sunflower and Marigold), with a prime focus on higher frequency behavior and analysis of reflection loss (RL) profiles for microwave applications. In this current investigation, the microwave absorption properties of two dried flower biomasses were prepared using a simple drying process. Microstructural study revealed unique canal and ribs cage structure in Sunflower and a highly porous flower-like structure along with agglomerated microspheres in Marigold biomass. Spectroscopic studies confirmed the presence of various functional groups and chemical constituents of both biomasses. The average dielectric constant and loss tangent vales of Sunflower and Marigold are found to be 2.61, 0.21 and 3.52, 0.23, respectively, using N5222B PNA Network Analyser. This variation in dielectric properties can be attributed to difference in their microstructure, carbon content, chemical constituents, and functional groups in naturally available biomasses. The reflection loss profiles were studied for both biomasses using CST Microwave Studio Simulator and a comparative analysis has done with wood biomass. Reflection loss profile of Sunflower was −18.80 dB with Effective Absorption Bandwidth (EAB) 5.38 GHz for 6 mm thickness and 7 mm shows highest EAB of 11.45 GHz which covers 82% of K-band. The reflection loss profile of Marigold shows −15.98 dB at 22.72 GHz frequency with EAB of 7.07 for 3 mm thickness.

This study explores the regulatory effect of heat-treatment temperature on the phase composition and luminescent properties of Mg₂SnO₄:Eu³⁺ phosphors prepared by microdroplet spray pyrolysis. A series of phosphors were synthesized, and their phase composition, morphology, and luminescent properties were systematically investigated via X-ray diffraction, fluorescence spectroscopy, and thermal stability testing. Results show that heat-treatment temperature is critical for phase regulation as pure cubic inverse spinel Mg₂SnO₄ is obtained at 1100 °C, while Mg₂SnO₄/SnO₂ biphasic composite structure forms at 900–1000 °C. All samples exhibit well-defined, monodisperse spherical particles with morphology unaffected by phase evolution. Under 254 nm excitation, biphasic composite phosphors show dominant Eu^{3+ 5}D₀ → ⁷F₁ orange emission with strong afterglow, while pure-phase samples exhibit weak Eu³⁺ red emission and green afterglow, confirming SnO₂ enhances Eu³⁺ orange emission. The optimal Eu³⁺ doping concentration is 0.02 mol; excessive doping induces concentration quenching. Afterglow decay follows a multi-exponential model attributed to multiple trap levels, and samples with different phases show distinct thermal quenching behaviors and stability.

Addressing current environmental challenges, a key issue in the ceramic industry is developing bulk electro-ceramic materials through low-cost and eco-friendly synthesis methods. Perovskite oxide has gained significant attention from researchers due to its high dielectric constant and its diverse applications in various fields of daily life. To tackle this, we have synthesized YCTO and YCTCVO, a prominent electro-ceramic material with a structure similar to CaCu₃Ti₄O₁₂ (CCTO), using an environmentally friendly semi-wet route and a readily available, low-cost titanium source. Y_2/3Cu₃Ti₄O₁₂ (YCTO) and Co, V-doped Y_2/3Cu₃Ti₄O₁₂ (YCTCVO) Ceramic were synthesized by semi-wet route. The confirmation of phases in Y_2/3Cu₃Ti₄O₁₂ (YCTO) and Co, V-doped Y_2/3Cu₃Ti₄O₁₂ (YCTCVO) ceramic were determined through X-ray diffraction (XRD) and Le Bail analysis of XRD data which emphasized an occurrence of single-phase formation of YCTO and YCTCVO ceramic along with a minor peak of CuO. Appropriate oxidation state of elements present in YCTCVO was confirmed by X-ray photoelectron microscopy (XPS). The average grain size and particle size of YCTO ceramic from Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) analyses on the respective scale of 4 μm and 0.5 μm were observed through ImageJ software and found to be 1.96 ± 0.50 μm and 0.33 ± 0.05 μm and for YCTCVO to be 4.03 ± 0.50 μm and 0.27 ± 0.05 μm, respectively. The presence of all elements respect to both ceramics were confirmed by Energy-dispersive spectroscopy (EDS) analysis. The average roughness (R_a) and a root mean square roughness (RMS) were calculated to be 0.46 μm (R_a), 0.57 μm (RMS) for YCTO, and 0.51 μm (R_a) and 0.63 μm (RMS) for YCTCVO, respectively. YCTO shows highest dielectric constant 88,395 at 523 K and 100 Hz while it was 1815 at 523 K and 100 Hz for YCTCVO ceramics. The tanδ of the YCTO and YCTCVO was noted approximately 7.0 and 3.6 at 100 Hz and 523 K. It was confirmed from above observations that the higher value of dielectric constant of YCTO ceramic in comparison to that of YCTCVO ceramic which might be due to lower RMS of YCTO ceramic observed through AFM studies, utilized in the application of energy storage devices.

Nanoflakes growth of Bi₂CdO₄ have been accomplished yielding tetragonal symmetric crystal structure through two-step chemical approach at room temperature as revealed by structural and morphological analysis. The liquid-configured electrochemical analysis of Bi₂CdO₄ grown on conducting stainless steel substrate was used as current collector and yields specific capacitance of 158.30 F/g (areal ~ 134.55 mF/cm²) at 5 mV/s with cyclic capacitive retention of 68.15% over 3000 CV cycles. Solid-state device configured through two analogous electrodes witnessed 1.5 V potential window with specific capacitance of 29.96 F/g (areal ~ 25.47 mF/ cm²) at 5 mV/s along with stability retention over 68.92% for 5000 CV cycles. Ragone’s curve specified energy density of 3.61 Wh/kg with 477.66 W/kg of power density. Illuminating a red LED panel and running small dc fan demonstrated the real-life application of a designed device-grade symmetric solid-state supercapacitor.