Journal of Electronic Materials最新文献

Perovskite quantum dots (PQDs) are promising for next-generation light-emitting diodes (LEDs) owing to their high photoluminescence quantum yields (up to 97.64%) and tunable emission (360–710 nm). However, toxicity, instability, and scalability limit their use. This review explores green synthesis and stabilization strategies for sustainable PQD-based LEDs. Eco-friendly methods, such as ethyl acetate-based synthesis, tartaric acid-assisted reprecipitation, and solvent-free ball milling, achieve high PLQYs (e.g., 88.24% for CH₃NH₃PbBr₃) with low environmental impact. Lead-free PQDs, such as Cs₃Bi₂Br₉, provide vibrant emission (400–560 nm) and stability for over 60 days. Stabilization techniques, including borophosphate glass encapsulation (94% photoluminescence (PL) retention after 240 h in water), silica coatings, and nontoxic ion doping (Mn²⁺, Bi³⁺), improve resistance to moisture and heat. Hybrid approaches deliver external quantum efficiency (EQEs) up to 27.1% and operational lifetimes of 1001.1 min for CsPbI₃ LEDs. These enable wide-color-gamut displays (128% NTSC), deep-blue LEDs, flexible optoelectronics, and anticounterfeiting applications. Recycling strategies using recovered PbI₂ support circular economy principles. These advancements enhance commercial viability through scalable, cost-effective synthesis, positioning PQDs for eco-conscious optoelectronic applications.

In this study, we explored the effects of chromium substitution on the structural, dielectric, and magnetic characteristics of Ba_0.92Sr_0.08Ti_1−xCr_xO₃ ceramics (where x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.25), which were synthesized using the solid-state reaction method. X-ray diffraction (XRD) analysis was used to determine the crystal structure and lattice parameters, while scanning electron microscopy (SEM) showed a decrease in grain size with increasing Cr concentration. Energy dispersive spectroscopy (EDS) confirmed the presence of Ba, Sr, Ti, O, and Cr elements. Dielectric measurements, including dielectric constant (ε_r) and tangent loss (tanδ), were conducted for different concentrations at various frequencies. Additionally, the remnant polarization (M_r) and coercive field (M_c), measured from the M–H curve at room temperature, demonstrated improved values. Improving these characteristics is essential for the creation of devices based on barium strontium titanate in fields like energy storage and optoelectronics.

Aqueous zinc-ion batteries (AZIBs) have emerged as one of the most promising options for contemporary energy storage systems owing to their inherent low cost, high safety, and environmental friendliness. However, developing high-performance AZIB cathode materials that meet the requirements for large-scale applications remains a considerable challenge. This study employed a straightforward hydrothermal method to efficiently synthesize Y³⁺ preintercalated hydrated vanadium oxide cathode material (VOH-Y). By introducing rare-earth Y³⁺ ions into layered V₁₀O₂₄·nH₂O, the original interlayer spacing was modulated; concurrently, this promoted the formation of a uniform two-dimensional nanosheet structure in VOH-Y, effectively optimizing the Zn²⁺ diffusion path and the distribution of insertion/extraction active sites, thereby enhancing diffusion kinetics. Therefore, the VOH-Y cathode delivered a specific capacity of 374.99 mAh g⁻¹ at 0.5 A g⁻¹ with 90.18% capacity retention after 200 cycles. This work highlights the importance of the Y³⁺ preintercalation strategy and provides new insights for developing high-performance AZIB cathode materials.

This study presents a simulation-based analysis of a lead-free perovskite (CH₃NH₃SnI₃) photovoltaic (PV) solar cell, focusing on the replacement of the conventional organic hole transport layer (HTL), Spiro-OMeTAD, with inorganic Sb₂S₃ (antimony trisulfide). The simulation results (using SCAPS-1D) show that the proposed solar cell structure, fluorine-doped tin oxide (FTO)/SrTiO₃/CH₃NH₃SnI₃/Sb₂S₃/Au), achieves considerably improved energy level alignment and stronger interfacial electric fields, effectively suppressing recombination losses. The influence of absorber layer, electron transport layer, and HTL thickness is analyzed with respect to the solar cell performance. In addition, the effect of absorber layer defect density is examined to simulate the proposed solar cell design under as many practical conditions as possible. We also investigate the dark current density–voltage (J–V) behavior for a thermal range of 290–330 K. The simulation results demonstrate notable performance gains corresponding to optimized solar cell design (absorber thickness = 1000 nm, ETL thickness = 150 nm, and HTL thickness = 200 nm)—an increase in open-circuit voltage (V_OC) from 1.11 V to 1.19 V, short-circuit current density (J_SC) from 28.85 mA/cm² to 33.62 mA/cm², and fill factor from 88.5% to 89.5%—yielding massively enhanced power conversion efficiency of 36.5% compared to 28.5%. The proposed solar cell design exhibits a significantly reduced dark current (~10⁻¹⁰ mA/cm² at 0 V) and superior thermal stability, establishing Sb₂S₃ as a nontoxic, stable, and cost-effective HTL for advancing efficient, environmentally sustainable tin-based perovskite solar cells.

The synthesis of high-performance photocathodes capable of converting seawater into clean hydrogen fuel represents a significant step toward advancing renewable energy technologies. In this work, we report the synthesis and evaluation of a novel nanosheet-based composite consisting of tungsten(VI) oxide sulfide and poly(o-aminothiophenol) (WO_3−XS_X/POATP). The nanosheets, with an average thickness of ~ 20 nm and a crystallite size of ~ 15 nm, exhibit uniform morphology and well-defined surface roughness, features that enhance light harvesting and facilitate charge transport. Optical studies indicate that the composite possesses a broad absorption range in the visible region with an estimated bandgap of 1.7 eV, making it suitable for solar-driven photocatalytic processes. The photocathode’s hydrogen evolution performance was tested using both natural seawater and an artificial seawater analogue. Under simulated sunlight, the hydrogen production rates reached 1.8 µmol h⁻¹ cm⁻² for natural seawater and 0.4 µmol h⁻¹ cm⁻² for artificial seawater, highlighting its strong capability for operation under real environmental conditions. Further analysis of the photocurrent density (J_ph) at −0.95 V under different photon energies revealed an increase from −0.028 mA cm⁻² at 1.7 eV to a maximum of −0.035 mA cm⁻² at 2.8 eV, followed by a slight rise to −0.036 mA cm⁻² at 3.6 eV. These variations confirm the high photoresponsiveness and sensitivity of the system to different light inputs. In addition to its excellent performance, the composite offers practical advantages such as the use of cost-effective materials, straightforward fabrication methods, and environmental compatibility. These attributes make the WO_3−XS_X/POATP nanosheet photocathode a strong candidate for scalable, sustainable hydrogen production directly from seawater, supporting global initiatives aimed at reducing reliance on fossil fuels and promoting clean energy adoption.

Allura Red (AR) is a red azo dye used in the health, beauty, pharmaceutical, and food industries. It is hazardous, causing an oxidative stress response and altering gene expression. As a result, it is critical to identify and quantify its concentration. In this work, bismuth oxide (Bi₂O₃), manganese dioxide (MnO₂), and manganese dioxide–bismuth oxide (MnO₂-Bi₂O₃) were synthesized using Mentha spicata leaf extract via a hydrothermal method. Subsequently, graphite electrodes (GE) modified with Bi₂O₃, MnO₂, and the MnO₂-Bi₂O₃ nanocomposite were developed as electrochemical sensors for detecting AR in food samples. The elemental composition, functional bond, crystal structure, morphology, and elemental mapping were confirmed using energy-dispersive x-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM), respectively. Differential pulse voltammetry (DPV) revealed that the anodic peak current demonstrated a linear relationship with AR concentrations between 1 μM and 5 μM. At a scan rate of 45 mV/s, the highest current response was achieved at the optimal potential range of −300 mV to 600 mV at pH = 11. A strong linear correlation between AR concentration and current was demonstrated by the electrochemical sensing probe, which exhibited sensitivity of 1.14 mA/μM/cm², 1.27 mA/μM/cm², and 1.28 mA/μM/cm², and corresponding limits of detection (LOD) of 0.7455 μM, 0.4462 μM, and 0.4084 μM for Bi₂O₃-GE, MnO₂-GE, and MnO₂-Bi₂O₃-GE, respectively, with correlation coefficients (R²) of 0.9834, 0.994, and 0.9924, respectively. Analytical factors were also studied, including sensitivity, linearity, repeatability, reproducibility, and stability. The real sample analysis in food samples (soft drinks and tomato sauce) yielded a satisfactory recovery percentage between 95% and 105%. Therefore, the experimental investigation of the MnO₂-Bi₂O₃ nanocomposite sensor confirmed that it is a promising material for evaluating AR in food safety.

Nitrogen-enriched graphene quantum dots (N-GQDs) were successfully synthesized via a one-step hydrothermal method using biomass as the carbon source and urea as the nitrogen dopant. The reaction was carried out in deionized water as a green solvent, promoting an environmentally friendly approach. The optical and structural properties of the resulting N-GQDs were characterized using UV–visible spectrophotometry, spectrofluorometry, attenuated total reflectance (ATR)/Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, x-ray diffraction (XRD), and transmission electron microscopy (TEM)/high-resolution TEM (HRTEM) analyses. The synthesized N-GQDs showed high quantum yield up to 28%. Notably, the synthesized N-GQDs showed enhanced sensitivity and distinct selectivity for Fe³⁺ ions over other metal ions, as evidenced by a significant fluorescence quenching effect upon Fe³⁺ addition. A linear decrease in fluorescence intensity was observed with increasing Fe³⁺ concentrations, indicating a broad detection range (0–600 μM) and a low detection limit of 0.023 μM. The interaction mechanism between Fe³⁺ and N-GQDs was further analyzed through density functional theory (DFT) calculations, revealing that nitrogen doping, along with oxygen-containing functional groups, plays a crucial role in stabilizing the coordination and electron transfer processes. Moreover, real water sample tests using tap water confirmed the practical applicability of N-GQDs, showing high recovery rates (96.8–103.4%), thereby demonstrating their reliability for detecting Fe³⁺ contamination. These findings suggest that N-GQDs derived from biomass offer a promising platform for the development of sustainable, low-cost, and effective fluorescent sensors for ferric ion detection.

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A flexible temperature and humidity sensor has been developed based on a composite of polyvinylidene fluoride (PVDF) and thermoplastic polyurethane (TPU). The sensor performance was optimized by introducing graphene quantum dots (NGQDs) and ionic liquids (TFSI) into the polymer composite. This type of humidity sensors has high sensitivity, fast response, and excellent stability, making it suitable for use in wearable health monitoring. The addition of TPU into PVDF facilitates the formation of a porous structure which has both a large specific surface area and high hydrophilicity. After optimizing the PVDF/TPU mass ratio to 5:3, such a humidity sensor displays 1.46 times higher sensitivity than that of pure PVDF film, with a linear response range of 10–90% relative humidity. The response time and recovery time are 7.67 s and 6.37 s, respectively. Owing to the improved hydrophobicity, the sensors also exhibit a good stability in a high humidity environment for > 10 days without significant degradation. Moreover, such a composite also has the capability to distinguish normal breathing from rapid breathing, demonstrating its potential in wearable health monitoring.

n-Butanol is one of the most well-known flammable and hazardous compounds that pose risks to both human health and safety. Thus, monitoring its concentration in the environment is critical. The demand for efficient toxic gas detection systems has driven advancements in gas sensor technology. Molybdenum diselenide (MoSe₂) has garnered significant attention owing to its ability to detect gases at room temperature. In this study, we present a novel sensor based on biofunctionalized magnetic nanoparticles integrated with MoSe₂ for detecting n-butanol. Biofunctionalized magnetite (CT-Fe₃O₃) was prepared using leaf extract obtained from Cinnamomum tamala and subsequently incorporated into a MoSe₂-based nanocomposite via a hydrothermal synthesis approach. The resulting MoSe₂-CT-Fe₃O₃ nanocomposite was employed to fabricate gas sensors and tested for n-butanol detection at various concentrations. The sensor demonstrated notable performance, achieving a response (ΔR/Rair %) of 47% for 5 ppm of n-butanol, highlighting its potential for room-temperature gas sensing applications.

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Bare and Ag@Sm-codoped ZnO nanobullets have been synthesized via a one-step hydrothermal technique with a 1-weight ratio of Sm and a variable 0.5–1.5 weight ratio of Ag. To investigate the actual role played by codoping, a comparative study of bare and Ag@Sm-codoped ZnO nanobullets to nanowires is carried out. The behavior of predicted simulation results and experimental results is the same. X-ray diffraction (XRD) patterns revealed that the nanobullets have grown along the (002) Bragg plane. The (002) peak positions of all codoped samples move towards the lower angle side compared with bare ZnO. The field emission scanning electron microscopy (FE-SEM) results of bare and 1 wt.% of Sm and 0.5 wt.%, 1.0 wt.%, and 1.5 wt.% of Ag codoped ZnO shows open-ended nanobullets with altered morphology from the nanobullets shape to an irregular nanowire shape with larger length and diameter. By increasing the doping content, the average diameter and size of nanowires increase, and the density of nanowires slightly decreases. The as-grown nanobullets to nanowire films were used as photo-electrodes in fabricating dye-sensitized solar cells (DSSCs). The cell made using a bare ZnO photoanode shows an overall power conversion efficiency (PCE) of 0.91%, and the cell made with 1 wt.% of Sm and 1.5 wt.% of Ag codoped ZnO photoanode shows a PCE of 4.43%, which is about 80% higher than that of the DSSC fabricated with bare ZnO. This increase in power conversion is either owing to rare-earth ions doping, which escalates the absorption of light in the wide range of the solar spectrum by up and down conversion, or because of the doping of Ag ions, which reduces the recombination of photo-generated electrons and boosts the high charge carrier mobility. These results show that high-power conversion DSSCs can be fabricated by modifying ZnO photoanodes with Ag and Sm.