Applied Nanoscience最新文献

The unique shape of tin (II) oxide (SnO₂) nanostructures in a colloidal solution is described. The nanostructures were synthesised using the pulsed Nd-YAG ablation technique, which entailed submerging small, high-quality tin particles in deionised water. The particles were coarsely crushed manually, filtered, and compacted into a solid tablet for 60 min using a 5-t hydraulic press. This production method utilised a pulse count of up to 200 laser shots, a wavelength of 1064 nm, spot size of 2.3 mm, focal length of 10 cm, and an energy of 500 mJ to examine the influence of surface shape on antibacterial activity levels. X-ray diffraction (XRD) analysis identified rhombohedral crystals mainly characterised by three Bragg peaks. Scanning electron microscopy (SEM) of the surface showed distinct and reasonably homogenous semispherical nanoparticles (NPs) rather than the expected porosity. The NPs exhibited an average size of 193.53 nm, in agreement with electron dispersive spectroscopy (EDS), which indicated that the oxygen-to-tin ratio closely approximated that of tin oxide (SnO₂). In addition, the vibrational spectra measured with a Fourier transform infrared (FTIR) spectrometer indicated the synthesis of amber-coloured SnO₂ NPs, confirming their formation by the preparation process, as well as their light scattering and absorption characteristics. In addition, using UV–visible spectroscopy, the resulting energy gap was 2.4 eV, within the normal range of energy gap for SnO₂. The generated NPs were discovered to suppress the growth of fungi and bacteria, indicating that they may prevent the development of these entities. Although the antibacterial and antifungal properties of tin oxide are not as well-known as those of silver or zinc oxide, this study demonstrated moderate antibacterial activity against the germs in question, making it a more secure and cost-effective alternative.

In this study, a Cu_xO–ZnO (Cu_xO:Cu₂O, CuO, Cu) nanocomposite was synthesized through a unique combination of electrochemical and solution reactions in which Cu containing compounds were synthesized from the electrolysis of a Cu anode along with redox processes in solution, accompanied with the formation of ZnO in solution that generated the Cu_xO–ZnO nanocomposite. The composition of ZnO in the material was controlled by changing the concentration of zinc sulphate in the reaction mixture. The morphology, composition, and structure of the resulting composite material were comprehensively analyzed through SEM, TEM, EDX, XRD and FTIR measurements. In addition, the dispersion properties of the material were investigated via DLS. Our findings indicated the successful formation of a Cu_xO–ZnO composite material, exhibiting a distinct morphology and a well-defined composition. The simultaneous electrochemical and solution reaction method has been proven to be an effective approach for tailoring the properties of material. The antifungal activity of the composite material demonstrated better antifungal efficacy than the individual Cu_xO and ZnO materials. This research contributed to the development of multifunctional composite materials with enhanced properties and opened new avenues for future investigations into their diverse applications.

This research examines the impact of a conductive polyaniline (PANI) thin film, cross-linked with formaldehyde, on the photoelectrochemical (PEC) capabilities of zinc oxide (ZnO) nanorods (NRs) for water-splitting purposes. The study involved a two-stage process: initially, ZnO NRs were generated on an indium tin oxide (ITO) substrate through a hydrothermal method; subsequently, the cross-linked PANI was produced via chemical polymerization and applied onto the ZnO NRs through spin coating. The crystal structure, surface morphology, and optical properties of the samples were characterized using XRD, SEM, and UV–Vis spectroscopy. The assessment of the PEC performance was carried out through CV and EIS. XRD analysis confirmed the existence of a hexagonal crystal structure of ZnO NRs. SEM analysis indicated a ZnO NRs average diameter of 164.5 nm. The band gap of the ZnO NRs, ZnO NRs/PANI, and ZnO NRs/PANI cross-linked formaldehyde are 3.04 eV, 3.02 eV, and 3.13 eV, respectively. The outcomes revealed that ZnO nanorods coated with cross-linked PANI exhibited the highest current density of 0.66 mA/cm² and a PEC efficiency of 0.41%. Furthermore, the EIS analysis verified that the cross-linked PANI improved the ionic conductivity of the ZnO NRs film. This study contributes to the comprehension of how cross-linked conductive polymers can boost the photoelectrochemical performance of semiconductor materials, presenting a potential strategy to enhance the efficacy of water-splitting devices.

This paper presents a proposed design of a communication nanodevice comprised of a circularly shaped nanoantenna operated in the optical frequency range of the electromagnetic spectrum corresponding to the wavelength range of 666.67–3000 nm. The suggested configuration of the nanoantenna combines a circular patch radiating element made of graphene material with a radius of 250 nm, mounted on a cube-shaped substrate layer made of silicon dioxide material with dimensions of (1600 nm × 1600 nm × 150 nm), and a partial ground plane nanolayer constructed from gold located at the bottom of the antenna. The proposed antenna was excited with a nanostrip feed line connected to a waveguide port. The CST simulator software package was used to study how it worked in the chosen frequency range. The results demonstrated that the proposed nanoantenna exhibits improved performance parameters in terms of the reflection coefficients, voltage standing wave ratio, gain, radiation efficiency, and wide bandwidth. The proposed optical nanoantenna is a tunable device that combines the advantages of graphene materials to create a high-performance nanoantenna appropriate for various wireless communication networks, including medical and healthcare systems.

Rapid detection of hydrogen gas leakage using flexible colorimetric sensor has been attractive attention in various chemical and automobile industries. However, an existing flexible colorimetric sensor have limitations concerning their lower sensitivity and mechanical strength. In this work, we have fabricated leather-based sensor material via spray coating of mesoporous PdO-TiO₂ nanocomposites (1:1, 2:1, 3:1 for PdO:TiO₂, size: 32–67 nm) on the leather surface and evaluated as a colorimetric hydrogen gas sensor at room temperature (25℃) with relative humidity (RH 10–90%) for the first time. The crystal structure, pore size, surface area, oxidation state, morphology and mechanical strength of prepared sensing materials (PdO-TiO₂ nanocomposite/PdO-TiO₂ leather) were characterized through X-ray diffraction pattern, X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett- Teller (BET), Scanning Electron Microscope (SEM) and Universal testing methods. The color difference (ΔE) of sensor materials was quantitatively calculated from CIELAB values and naked eye readout. The obtained results indicated that the sensor material exhibited rapid hydrogen gas detection capabilities by color changing from brown to black (ΔE = 8.71) when exposed to hydrogen gas (4%, H₂). Among the sensor materials, PdO-TiO₂ (2:1) nanocomposite-coated leather can detect 10 ppm hydrogen gas with higher selectivity within 10 s due to the large surface area (59.70–113.19 m²/g) of the mesoporous nanocomposite. The present study will provide a global strategy for fabricating high-performance flexible colorimetric sensor for detecting hydrogen gas in the chemical and automobile industry.

This research focuses on improving the performance of piezoelectric energy harvesters (PEHs), which convert ambient kinetic energy into electricity. One of the primary challenges with piezoelectric harvesters is their high resonant frequencies, which often do not align with the lower natural frequencies of ambient vibrations, limiting their efficiency. The goal of this research is to propose a new technique to optimize the design of PEHs, enhancing voltage output and power conversion efficiency. The proposed method combines an Arithmetic Optimization Algorithm to optimize the harvester’s dimensions with a Dual Temporal Gated Multi-Graph Convolution Network (DTGMGCN) to forecast resonant frequency and harvested voltage. The principal objective is to reduce resonant frequency errors and enhance energy conversion efficiency. The results, implemented on a MATLAB platform, demonstrate that the proposed method outperforms the existing techniques, such as robust chaotic Harris Hawk optimization, K-Nearest Neighbor Algorithm, and Heaviside Penalization of Discrete Material Optimization. The existing techniques show errors of 0.04%, 0.06%, and 0.08%, while the proposed method achieves an error of only 0.02%. Additionally, in terms of efficiency, the proposed method reaches 98%, significantly higher than the 65%, 78%, and 85% achieved by the existing techniques. These findings indicate the efficiency of the proposed approach in improving the design and performance of piezoelectric energy harvesters, offering a promising solution for more efficient energy harvesting systems.

The effective removal of synthetic dyes from wastewater remains a significant environmental challenge. This study investigates the potential of carbonated pineapple peel waste, integrated with magnetic nanoparticles (PMNPs), for the adsorption-based removal of Congo red (CR) and methylene blue (MB) dyes. Various characterization techniques, including SEM, FTIR, and EDS, were used to analyze PMNPs before and after adsorption, while XRD, BET, VSM, and TGA were applied to assess the properties of pure PMNPs and their suitability for adsorption. The PMNPs exhibited a needle-like morphology and a high surface area of 6.836 m²/g, enhancing their dye adsorption capacity. At concentrations of 1.5 and 1.25 g/L, PMNPs achieved removal efficiencies of 93.15% for CR and 95.99% for MB. Thermodynamic analysis revealed the adsorption process to be spontaneous and exothermic. Computational modeling demonstrated that the Langmuir isotherm best described the adsorption process (R² = 0.9930 for MB and 0.9891 for CR), while pseudo-first-order kinetics indicated physical adsorption. Artificial neural network (ANN) models further validated the experimental results, showing high prediction accuracy (R = 0.9948 for MB and 0.9939 for CR). The PMNPs retained efficient performance after six reuse cycles, highlighting their reusability. This novelty of the research demonstrates the potential of PMNPs as a sustainable adsorbent and provides insights into optimizing adsorption processes through computational modeling.

The demand for sustainable and eco-friendly materials has promoted studies over the years to explore different polymeric materials that meet requirements such as biodegradability and sustainability. In this context, biopolymer materials based on cellulose nanoparticles and starch from different botanical sources have been investigated, aiming to achieve satisfactory performance. The present study aims to develop and characterize cassava starch foams based on density, scanning electron microscopy (SEM), and three-point flexure tests, and to evaluate the effect of cellulose nanofibers obtained from palm mesocarp fibers using the ultrafine friction grinding method after different processing times, characterized by X-ray diffractometry (XRD), microscopy, and chemical composition, as a reinforcing filler. The chemical composition and scanning electron microscopy revealed the effectiveness of the cellulose isolation process, with  the analysis of the chemical composition revealing a cellulose content of 55.70% in the fibers after pulping and bleaching, in addition to changes in the visual characteristics of the material after the process aimed at isolating the cellulose. After grinding, XRD showed an increase in crystallinity (76.1% at the maximum grinding time), along with typical microscopy images of cellulose nanofibers. The analysis of the obtained nanocomposites provided insights into the role of these nanostructures in the thermo-expanded starch matrix, indicating that the nanofibers promoted changes such as an increase in mechanical properties and crystallinity, which contributed to improving overall mechanical performance. A 67.48% increase in flexural strength was achieved for the formulation with cellulose nanofibers that underwent 150 min of grinding, without causing major variations in density.

In recent years, the advancement of nanotechnology has created a great impact on the textile industry. Adhering to nanoscale levels, fabric surfaces have a wide variety of uses including ultraviolet (UV) protection, antibacterial resistance, wrinkle resistance, and flame retardance. In this work, selenium nanoparticles were synthesized and coated over three distinct cotton-woven fabrics (i.e.) organic, poplin, and muslin cotton fabrics. The respective coated fabrics were examined using X-ray diffraction analysis (XRD) which exhibits high crystallinity with an average size of 11 nm. The existence of cellulose peak has been confirmed from FTIR analysis. SEM images illustrate that the selenium nanoparticles have been coated on the respective fabrics. According to measurements of water contact angle, cotton fabric from muslin exhibits higher levels of hydrophobicity than other types. Colorfastness study has revealed that poplin cotton discloses higher color strength than others. Washing durability and tensile properties of the coated fabric has also been examined. The results of the antibacterial test showed that the presence of selenium nanoparticles significantly enhanced the antibacterial performance against three different bacterial strains, including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli using the disk diffusion method and its Zone of Inhibition (ZOI) were measured. Out of the three fabrics, poplin cotton has superior antibacterial properties.

Nanoceramics are distinguished by their exceptional mechanical qualities, including considerable strength, good toughness, and high fatigue resistance. Utilizing a green combustion technique, we successfully developed these nanoceramics and characterized them comprehensively using UV–Vis, XRD, EDAX, TEM, and XPS analyses. Our findings indicate the formation of nanocomposites with distinct cubic phases of NiO and ZrO₂, confirming their polycrystalline nature through SAED and XRD. The developed nanoceramics were innovatively applied for bacterial cell lysis to extract intracellular components. Nevertheless, the previously published microbial cell lysis approaches are insufficient for cell disruption due to the cell firmness. Thus, a nanoceramic mediated protein harvesting methodology was proposed from Bacillus subtilis CP-66 cells and promising results (0.447 mg/ml) were obtained within 25–50 min of the abstraction process. This nanoceramic is also explored for their broad-spectrum antibacterial activity against three human pathogenic bacterial strains. This work highlights the many uses of our nanoceramic material in advanced materials science and emphasizes its potential in industrial and healthcare applications.