Journal of Electronic Materials最新文献

This study highlights the coupling of photocatalytic and piezocatalytic activity, potentially improving the efficacy of synthesis under both solar and visible light conditions. The melt-quench technique was employed to synthesize a single-phase Bi₂VO_5.5 (BV) sample. The orthorhombic Bi₂VO_5.5 phase was established using Raman spectroscopy and x-ray diffraction. Analysis via scanning electron microscopy demonstrated the irregular morphology of the synthesized Bi₂VO_5.5. X-ray photoelectron spectroscopy revealed the different elemental oxidation states that were present. During the synergetic piezo-photocatalysis experiment under visible light in methylene blue dye, degradation efficiency of (sim )63% within 180 min was achieved. The kinetic rate constant was investigated in relation to the concentration of the dye. The kinetic rate constants for the BV sample under sunlight were 0.01168 min⁻¹ and 0.02183 min⁻¹ for photocatalysis in 90 min and piezo-photocatalysis in 30 min, respectively.

We report a sustainable and efficient route for the fabrication of formamidinium lead iodide (FAPbI₃) perovskite solar cells (PSCs) via a green solvent-based two-step deposition process. In this method, PbI₂ is dissolved in dimethyl sulfoxide (DMSO), a less toxic solvent than traditional dimethylformamide (DMF), and spin-coated, followed by the deposition of FAI from isopropanol (IPA). Furthermore, surface passivation using a fluorinated interlayer, 4F-phenethylammonium iodide (PEAI), improves device morphology and charge transport, resulting in a power conversion efficiency (PCE) of 19.61.%. Comprehensive structural, optical, and electrical characterizations confirm enhanced crystallinity, reduced trap density, and suppressed hysteresis in treated devices. This environmentally benign and industrially scalable process paves the way for the commercialization of high-performance, low-toxicity perovskite photovoltaics.

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The structural stability of multivacancies in monolayer gallium nitride has been studied using density functional theory (DFT) with the generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof for the exchange–correlation functional. The supercell consisting of 72 atomic sites is used to model the multivacancies, with all atoms in the supercell relaxed during optimization. The multivacancies are created by removing a pair of Ga–N atoms sequentially from the center of the supercell, following the part-of-hexagonal-ring method. The multivacancies modeled are monovacancy to hexadecavacancy. The stability of multivacancies is analyzed through the formation and dissociation energies. From the calculated energies, we conclude that hexa- and decavacancies are stable multivacancies, indicating that multivacancies in monolayer GaN tend to agglomerate to hexa- and decavacancies. To show the effect of atomic relaxation, we compare our DFT results with the dangling bond counting model, which ignores atomic relaxation. The symmetry of each defective system is discussed.

Graphical Abstract

Nickel oxide and aluminum-doped zinc oxide thin films were successfully deposited using pulsed laser deposition. Two nickel oxide thin films were grown at deposition pressure of 10 mTorr (≈ 1.33 Pa) and 20 mTorr (≈ 2.66 Pa). The prepared NiO thin film was successfully characterized using x-ray diffraction, ultraviolet (UV) spectroscopy, and Hall measurement techniques. The thermoelectric measurements were carried out using an in-house-developed thermoelectric setup. The Seebeck coefficient values for the nickel oxide thin films prepared at 20 mTorr and 10 mTorr were found to be nearly the same, at approximately 0.018 mV/K. The power factors at 20 mTorr and 10 mTorr for the nickel oxide thin films were estimated to be 0.00008424 mW cm⁻¹ K⁻² and 0.0000312 mW cm⁻¹ K⁻², and the figure of merit was estimated as 0.125 and 0.046, respectively.

Graphical abstract

Chromium niobate (CrNbO₄), molybdenum niobate (Mo₃Nb₂O₁₄), titanium niobate (TiNb₂O₇), and binary oxide based on Nb₂O₅ and WO₃ were synthesized by low-temperature underwater plasma. The electrode materials (Nb, Mo, Cr, Ti, and W) were used as precursors. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric (TG) analysis, and impedance analysis were used to characterize the obtained materials. The results of XRD showed that in the case of combining electrodes from niobium and molybdenum and chromium and titanium, niobates are formed, and in the niobium-tungsten pair, a mixture of oxides is formed. The results of dielectric measurements showed that the obtained materials have high dielectric constants (ε_r > 10–60 at f > 1 kHz). Thermal analysis data allowed us to propose a mechanism for the formation of niobates in underwater plasma conditions.

The growth of large-area, continuous, and crystalline vertically grown MoS₂ nanostructures is always highly challenging. Morphological tuning of atmospheric pressure chemical vapor deposition (APCVD)-grown MoS₂ nanostructures can be achieved via precise control over deposition parameters, demonstrating engineered properties suitable for gas sensing applications. In the present work, a one-step APCVD growth procedure is developed for optimized morphological evolution, which allows the synthesis of large-scale cross-linked vertically grown MoS₂ nanopetal structures with high crystallinity and phase selectivity. The optimized morphological tuning enabled the transformation from MoO₂/MoS₂ nanoplates into hybrid MoO₂/MoS₂ nanostructures, leading to the growth of V-MoS₂ nanopetals over a SiO₂/Si substrate by controlling sulfur concentration with the help of sulfur precursor temperature and Ar gas flow. Field-emission scanning electron microscopy (FESEM) clearly shows the evolution of the morphology in APCVD growth. Raman spectra and x-ray diffraction clearly support the synthesis of vertically grown cross-linked MoS₂ nanopetals and structural and phase transformation from MoO₂/MoS₂ nanoplates to V-MoS₂ nanopetals. Current–voltage (I–V) characteristics demonstrate an increase in current conduction as the morphology changes from MoO₂/MoS₂ nanoplates to V-MoS₂ nanopetals and shows ohmic behavior. The edge-enriched V-MoS₂ nanopetals demonstrate the highest sensitivity of 61.78% for 100 ppm NO₂ at 100°C operating temperature. The relative response of the V-MoS₂ nanopetal sensor increases from 16.93% to 61.78% as the gas concentrations of NO₂ increases from 1 ppm to 100 ppm at 100°C operating temperature. This optimized nanosensor demonstrates the highest selectivity towards NO₂ gas, with a limit of detection (LOD) of 1 ppm and a fast response of 22 s.

A comprehensive study of the capability for graphene doping in a lizardite/graphene heterostructure has been conducted. Formation energy calculations of the 12 heterostructures exhibit the chemical stability of all the conformations. The electronic properties of doped lizardite/graphene heterostructures preserve the electronic characteristics of graphene while inducing a p-type/n-type doping due to the substitutional impurity of lizardite. The modified electronic properties of the heterostructures resulting from doping have been thoroughly examined. Moreover, the enhanced conductivity of the heterostructures confirms the doping of graphene and widens the scope of the applicability of graphene.

Tungsten carbide (WC) is an alloy powder with excellent performance. However, there are significant technical bottlenecks in the high-content WC composite cladding process. Owing to the density difference between the WC hard phase and the metal matrix, WC particles tend to deposit and cluster during the cladding process, forming a concentrated zone at the bottom of the coating. This can induce cracks, pores, and other defects, resulting in uneven performance of the cladding layer and reducing the service life of the workpiece by 40–50%. Research indicates that the alternating magnetic field-assisted process generates Lorentz forces to implement electromagnetic stirring, thereby achieving a more uniform distribution of WC particles. This process enhances heat and mass transfer efficiency and promotes grain refinement. In this paper, a numerical model of the laser cladding process of 42CrMo with nickel-based WC60 composite powder was established. The influence of stress-fatigue laws on the cladding process under no magnetic field and with magnetic fields of 20 mT, 40 mT, and 60 mT was calculated respectively. Scanning electron microscope (SEM), x-ray diffraction (XRD), and microhardness observations were conducted to examine the microstructure morphology, phase composition, and hardness of the cladding layer. Based on the test results, an internal model of the cladding layer was established, and the derived distribution of internal stress was calculated. Calculations show that alternating magnetic fields significantly affect the sedimentation and stress distribution of WC particles. The stronger the field, the more WC particles float. The smaller the stress derived, the higher the hardness.

Zinc oxide (ZnO) nanostructures, from nanorods to nanofibers, were synthesized using a straightforward hydrothermal method. Samples were synthesized with different growth times of 5 h, 12 h, and 20 h, as well as different titanium dioxide (TiO₂₎ atomic percentages (0, 3, and 6 at%). Characterization was performed by scanning electron microscopy (SEM) for morphological study, while chemical composition was analyzed using x-ray photoelectron spectroscopy (XPS) and x-ray energy dispersive spectroscopy (EDS). Optical properties were measured by Raman spectroscopy at room temperature. The formation of ZnO nanorods and nanowires was confirmed trough SEM and the chemical composition by EDS and XPS. In this work, we propose a controlled growth mechanism of ZnO nanorods using TiO₂ as nucleation centers without affecting the lattice parameters or doping. SEM images reveal a physical effect on nanostructure growth due to the influence of TiO₂ nanoparticles on the zinc oxide formation process. After 20 h of growth, exceptionally long ZnO nanofibers were obtained, with diameters ranging from 20 nm to 25 nm and lengths in the micrometer scale (growth rate about 8 nm/m). The nanorods produced by this method exhibit very controlled growth, which makes them promising for applications in ZnO-based gas sensors, due to the increased surface area. Their vertical and ordered arrangement is particularly advantageous for optimizing the sensing process.

This study presents the development and characterization of P3HT: Borophene-ZnO p-n junction-based organic thermoelectric generators (OTEGs), demonstrating superior performance compared to P3HT-ZnO systems. The incorporation of borophene significantly enhances electrical conductivity (reaching ~ 12 × 10⁴ S/cm) while maintaining favorable Seebeck coefficients (~100–200 µV/K), particularly in the 400–500 K range, due to borophene's 2D conductive network that bridges the organic-inorganic interface. Structural analyses confirm the crystalline quality of borophene and its effective integration with P3HT. At the same time, thermoelectric tests show that the ternary composite achieves higher power factors than the binary P3HT-ZnO system, making it a promising candidate for mid-temperature waste heat recovery applications. The work advances organic thermoelectrics by optimizing the synergy between conductive 2D materials (borophene), polymers (P3HT), and metal oxides (ZnO) through innovative solution processing and junction engineering.