Journal of Materials Science: Materials in Electronics最新文献

In this study, a combined theoretical and experimental investigation was carried out to assess the NH₃ sensing performance of graphene oxide (GO), reduced graphene oxide (rGO), and their manganese-doped rGO (Mn–rGO). Theoretical results indicated that GO exhibited limited sensitivity toward NH₃ adsorption, while rGO showed improved adsorption behavior. Based on these findings, rGO was chosen as the substrate for experimental sensing studies. Further theoretical analysis revealed that Mn-rGO exhibited the most favorable structural and electronic properties for NH₃ interaction among the materials evaluated. Experimentally, GO was synthesized using the Hummer’s method, and Mn-rGO was fabricated via a hydrothermal route. The successful formation and composition of the materials were confirmed through a range of characterization techniques, including XRD, FTIR, FESEM, EDS, HRTEM, and UV–Vis spectroscopy. Gas sensing performance was evaluated using I–V measurements, which showed good agreement with theoretical predictions. The sensitivity of rGO and Mn–rGO to NH₃ gas was found to be 60% and 2480%, respectively. The remarkably high sensitivity of Mn-rGO highlights its strong potential as a promising material for NH₃ gas sensing applications.

Precise control of oxygen vacancies is critical for optimizing the electrical performance and stability of amorphous oxide thin-film transistors (AOS TFTs). Amorphous Ga–Zn–Sn–O (a-GZTO) is a promising material in this regard, with Ga incorporation expected to modulate oxygen vacancy concentration and improve device reliability. This study systematically investigates the impact of Ga content on the electrical properties and thermal stability of a-GZTO TFTs. The characteristics of a-GZTO thin-film transistors (TFTs) were investigated by varying the gallium (Ga) concentration to 0 wt%, 1 wt%, and 2 wt%, enabling a systematic comparison of their electrical performance. A-GZTO TFTs were fabricated using radio frequency (RF) magnetron sputtering at room temperature. As the Ga ratio increased, the device’s threshold voltage (V_th) shifted upward from 4.84 to 9.38 V, while the mobility decreased from 22.9 to 17.7 cm²/V·s. Additionally, UV–visible spectroscopy revealed that higher Ga content enhanced transmittance in the ultraviolet region, indicating improved optical properties. To further examine these electrical characteristics, X-ray photoelectron spectroscopy (XPS) was employed, which confirmed that increased Ga content resulted in a reduction of oxygen vacancies. Transmission line measurement (TLM) analysis also validated a decrease in carrier concentration with higher Ga ratios, supporting the observed decline in mobility. Device stability was further assessed under temperature stress (TS), and based on the TS results, activation energy (E_a) and density of states (DOS) were extracted. These findings suggest that increasing Ga doping enhances thermal stability and optical transparency by reducing oxygen vacancies, although it adversely affects certain electrical properties due to decreased carrier concentration.

Water contamination by antibiotics, heavy metals, and synthetic dyes poses a serious threat to both human and environmental health. In this work, we introduce a sustainable cerium-based Prussian blue analogue/biocarbon hybrid (Ce-PBA/NPC) photocatalyst, synthesized using jackfruit-peel-derived N, P-doped carbon, for broad-spectrum degradation of ciprofloxacin (CIP), hexavalent chromium (Cr (VI)), and crystal violet (CV) under visible-light irradiation. The hybrid design strategically couples the redox-active Ce³⁺/Ce⁴⁺ centres in Ce-PBA with the high conductivity, hierarchical porosity, and defect-rich active sites of N, P-doped biocarbon. Textural and optical evaluations revealed a markedly increased surface area (186.7 m²g⁻¹), enlarged pore volume (0.42 cm³ g⁻¹), and a narrowed band gap (1.95 eV) for the composite compared with pristine Ce-PBA. These findings indicate that the composite possesses more efficient light harvesting and improved charge separation. As a result, the Ce-PBA/NPC photocatalyst achieved degradation efficiencies of 92% for CIP, 88% for Cr (VI), and 95% for CV within 120 min, with apparent rate constants 3–4 times higher than those of the individual components. The composite also maintained high activity in binary and ternary pollutant systems, demonstrating strong resistance to competitive inhibition. These findings highlight the Ce-PBA/NPC hybrid as a durable, eco-friendly, and high-performance photocatalyst for visible-light-driven remediation of multi-target contaminants in wastewater.

In this study, high-performance MIS Schottky photodiodes were using a novel Sr-modified ZrO₂ interfacial layer synthesized via the Jet Nebulizer Spray Pyrolysis (JNSP) technique. Sr incorporation (3, 6, 9wt%) systematically tailored the structural and optical characteristics of ZrO₂, enabling a transition to highly uniform cubic-phase films with refined crystallite size (17 to 10 nm), enhanced UV absorption, and bandgap narrowing to 3.90 eV. FESEM, EDAX and XPS analyses confirmed the formation of smooth, defect-minimized surfaces with stable Zr⁴⁺ O²⁻ Sr³⁺ bonding environments. The optimized Cu/ZrO₂@Sr/n-Si diode (9 wt% Sr) exhibited markedly improved transport behavior, achieving an ideality factor of 3.63, barrier height of 0.76 eV, and significantly enhanced photosensitivity, responsivity, and quantum efficiency, alongside a detectivity of 4.94 × 10⁷ Jones. This work demonstrates, for the first time, that Sr-engineered ZrO₂ acts as a highly effective high-k interlayer, enabling substantial performance enhancement over undoped and RE-doped counterparts, establishing a new pathway for next-generation UV photodetectors and MIS-based optoelectronic devices.

The increasing discharge of persistent and toxic organic dyes into industrial wastewater necessitates the development of efficient, economical, and environmentally sustainable treatment strategies. In this study, a high-performance photocatalyst was synthesized as a ternary TiO₂–ZnO/Graphene Oxide (NC ZnO) nanocomposite. The novelty of this work lies in the strategic combination of TiO₂ and ZnO nanoparticles onto high-surface-area graphene oxide (GO) sheets, forming a Type-II heterojunction that effectively suppresses the rapid recombination of photoinduced electron–hole pairs and enhances charge separation efficiency. The NC ZnO was synthesized via the sol–gel method because it is superior at achieving molecular-level homogeneity and controlling the morphology of the metal oxides at low processing temperatures, which is critical for preserving the integrity of the GO nanosheets. Furthermore, Moringa oleifera seed extract was utilized as a natural reducing and stabilizing agent, introducing a green and sustainable synthesis route. Comprehensive characterization of NC ZnO confirmed the successful formation of the ternary heterostructure. Hexagonal wurtzite structure, crystallinity, and functional groups of the samples were characterized via X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The photocatalytic activity of the optimized NC ZnO was evaluated for the degradation of Methylene Blue (MB) and Carbol Fuchsin (CF) dyes under visible light irradiation, achieving degradation efficiencies of 75% and 72%, respectively, within 90 min. The developed NC ZnO nanocomposite thus represents a promising, cost-effective, and eco-friendly photocatalyst for the efficient remediation of dye-polluted industrial effluents.

Developing electrode materials that simultaneously provide high redox activity, rapid charge transport, and long-term stability is crucial for advancing next-generation supercapacitors. In this study, a series of metal–organic frameworks (MOFs), including Ni-MOF, Fe-MOF, bimetallic Ni/Fe-MOF, and Zn-doped Ni/Fe-MOF, were rationally synthesized and comprehensively evaluated to establish clear correlations between their structural features and electrochemical behavior. Among these, the Zn-doped Ni/Fe-MOF exhibited the most outstanding electrochemical behavior, attributed to the synergistic effects of dual-metal coordination and Zn incorporation, which collectively enhanced electrical conductivity and increased the accessible electroactive surface area. When applied as the positive electrode in an aqueous asymmetric supercapacitor (ASC) using activated carbon (AC) as the negative electrode and 2M KOH electrolyte, the Zn-doped Ni/Fe-MOF delivered a high specific capacitance of 102.31 F g⁻¹ at 1 A g⁻¹ and retained 71.03 F g⁻¹ at 10 A g⁻¹. The assembled ASC also achieved an energy density of 23.45 Wh kg⁻¹ at a power density of 803.77 W kg⁻¹, along with excellent cycling stability, maintaining 89.42% capacitance retention and ~ 99% coulombic efficiency over 5000 cycles. These findings highlight Zn-doped Ni/Fe-MOF as a promising electrode material for high-performance aqueous ASCs, offering a balanced combination of energy density, power capability, and operational durability.

This study investigates the photoconductive response of Au-doped TiO₂ thin films under ultraviolet (UV) illumination, with a focus on changes in electrical resistance as a detection mechanism. Thin films with varying gold nanoparticle distributions—on the surface and within the TiO₂ matrix—were fabricated using magnetron sputtering and thermal oxidation techniques. Under UV exposure, all Au-doped samples exhibited a significant, rapid, and reversible decrease in resistance, attributed to the generation of photoinduced charge carriers in TiO₂ and localized surface plasmon resonance (LSPR) effects from the incorporated Au nanoparticles. Among the samples, the configurations with Au located at the surface (Top-Au) and embedded within the film (Mid-Au) exhibited the most efficient photo response. Best response values, sensitivity are 6.8% and 6.5%, rise/fall times are 0.48/0.12 and 0.38/0.29 for Mid-Au and Top-Au, respectively. The results confirm that resistance modulation in these nanostructured films provides a reliable, low-power approach for real-time UV photodetection. This work highlights the potential of plasmon-enhanced oxide semiconductors in the development of next-generation optoelectronic sensors.

In this present work, nanoparticles of Zn-doped SnO₂ nanostructures were synthesized using a low-cost solution combustion synthesis method. The structural analysis and morphological properties with elemental composition of synthesized samples were characterized via X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) respectively. XRD investigations confirm the tetragonal rutile structure with a reduction in average crystallite size from 8.63 nm to 7.06 nm with an increase of Zn²⁺concentration. FESEM with energy dispersive X-ray spectroscopy (EDS) confirms the formation of nanoparticles without any impurity. UV–Visible studies show a reduction in band gap energy values from 3.71 eV to 3.38 eV with an increment in concentration of Zn. Fourier transform infrared spectroscopy (FTIR) corresponds to O–H, C–H, Sn–OH, and Sn–O–Sn functional groups and confirms the creation of pure phase SnO₂. Photoluminescence spectra (PL) of Zn-doped SnO₂ nanostructures analyze the near band edge emission or UV emission at 454 nm and a green emission at 524 nm, confirming the excess of oxygen vacancies within the host structure. Raman spectra also confirm the abatement of crystallite size and existence of flaws like oxygen vacancies. These defects significantly influence the interaction of gas molecules with the surface of the sensing layer. The I–V (current–voltage) characteristics of the paper-based sensing device fabricated using Zn-doped SnO₂ nanostructures were examined to investigate its response in the ammonia environment with regard to varying exposure time. An increase in electric current was observed at a specific applied voltage when the Zn-doped SnO₂ nanostructured layer on Whatman paper was exposed to ammonia fumes, demonstrating its oxidizing nature. Only qualitative mode is used in these sensing studies.

The copper europium oxide (({text{Eu}}_{2}{text{CuO}}_{4})) cuprate was synthesized by the solid-state reaction method and investigated in terms of its structural as well as linear and nonlinear optical properties. X-ray diffraction, combined with Rietveld refinement, Rietveld refinement confirmed that the XRD pattern corresponds to the ({text{Eu}}_{2}{text{CuO}}_{4}) phase. The lattice parameters for ({text{Eu}}_{2}{text{CuO}}_{4}) were determined to be a = 3.902(2) Å and c = 11.905(6) Å, in accordance with reported data for T′-type cuprates, while revealing slight lattice distortions associated with oxygen stoichiometry. Raman spectroscopy further confirms the stabilization of T′-phase through the identification of the characteristic A_1g and B_1g vibrational modes. The direct optical bandgap was evaluated to be 1.55 ± 6.4 × 10^–4 eV, consistent with the 1.45–1.70 eV range reported for ({text{Eu}}_{2}{text{CuO}}_{4}) and other T′-type cuprates, while showing enhanced absorption near the band edge. The refractive index (n), dielectric function (ε), as well as the real and imaginary parts of the optical conductivity (({upsigma }_{1}) and ({upsigma }_{2})) were determined. Furthermore, optical dispersion was analyzed using the Wemple–DiDomenico model to extract oscillator parameters and to evaluate the third-order nonlinear optical susceptibility (χ³). The χ³ value obtained, previously scarcely investigated, represents an original contribution of this work and highlights the good potential of Eu₂CuO₄ for advanced optoelectronic applications.

In this research, cobalt ferrite (CoFe₂O₄) nanoparticles were synthesized via the thermal decomposition method, and their magnetic hyperthermia performance was evaluated under high strength alternating magnetic fields. The structural, morphological, and magnetic properties of the nanoparticles were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and vibrating sample magnetometer (VSM). The specific absorption rate (SAR) values of CoFe₂O₄ nanoparticles (S1, S2, and S3) increased with increasing magnetic field strength. At a magnetic field of 400 Oe and a frequency of 300 kHz, the maximum specific absorption rate (SAR) values recorded were 334.48, 362.35, and 1003.44 W/g for samples S1, S2, and S3, respectively. Notably, sample S3 exhibited the highest specific absorption rate values at both (400 Oe, 300 kHz) and (300 Oe, 400 kHz) compared to the other samples.