Applied Nanoscience最新文献

The high-performance optical receivers were fabricated by depositing an ultra-thin film (antimony trioxide, Sb₂O₃) on a porous Si (p-Si) substrate using the laser ablation method. The p-PSi layer was obtained by electrochemical etching, and the XRD results showed that it had a crystalline orientation with main diffraction peaks at 28.84°, 33.09°, and 69.39° corresponding to the (111), (200) and (400) planes of silicon wafers. AFM displayed a nanostructured surface with pyramid-shape hillocks and isolated Si-pillars (features favourable to quantum confinement), whereas PL measurements have confirmed an enhanced bandgap: 1.77 eV (in comparison with the bulk Si value 1.11 eV). In the Sb₂O₃ film, only the cubic senarmontite phase was identified, which also shows sharp XRD peaks suggesting high crystallinity. AFM and SEM observations exhibited a relatively rough surface with RMS = 17.96 nm, average grain size = 91.59 nm, and the agglomeration of the NPs (minimum-particle-size ≈ 27.83 nm). Characteristic Sb₂O₃ vibration modes were confirmed with FTIR, and the optical bandgap was measured to be 3.49 eV. The Ag/Sb₂O₃/PSi/p-Si/Ag heterojunction photodetector exhibited a remarkable optoelectronic performance. High peak responsivities of 0.34, 0.47, and 0.88 mA/W are achieved at the wavelength of 352 nm, 650 nm, and 800 nm, respectively; specific detectivity up to 1.26 × 10¹³Jones is obtained; carrier lifetime was measured to be the longest time (1.92 µs) among reported Schottky based RSD device platforms using the C–V technique signaled an abrupt junction that suggest their broad debut for broadband detection purposes.

This research combines Density Functional Theory calculations and equation of state modelling to explore how pressure affects the properties of TiO₂, ZnO, and Fe₂O₃ nanoparticles up to 25 GPa. Under pressure, the crystal structures compress, causing the atoms to pack together more tightly, and the overall volume decreases. Elastic constants, which indicate stiffness, increase with pressure, and the materials remain mechanically stable. Thermodynamic properties, such as the Debye temperature and thermal expansion, were derived using a quasi-harmonic approach, with Density Functional theory and equation of state results aligning quite well. Also, the energy band gaps narrowed as pressure increased, showcasing how pressure can be used to fine-tune electronic characteristics. Overall, good agreement between Density Function Theory, Equation of State, and experimental data supports the use of these nanomaterials in high-pressure optoelectronics and thermomechanics.

Incorporating Renewable Energy Sources (RES), mainly solar energy into Brushless Direct Current (BLDC) motor fed Electric Vehicles (EVs) are becoming progressively popular as the world moves more quickly towards clean and sustainable transportation. However, EVs’ dynamic load demands and the erratic nature of solar radiation make it difficult to maintain control dependability, energy efficiency and peak performance. In order to address these issues, a refined photovoltaic (PV)-driven Trans Quasi Z-Source Modified SEPIC-Luo (TQZSMSL) converter and energy management system is presented in this study. A Lyrebird Optimisation Algorithm (LOA)-optimized Radial Basis Function Neural Network (RBFNN) is the main goal of proposed framework, guaranteeing real-time adaptation to varying solar input. A TQZSMSL converter is used in conjunction with this, offering reliable and adaptable voltage conversion capabilities to sustain a constant DC output. The BLDC motor speed is regulated with the aid of Proportional Integral (PI) controller. Also an Internet of Things (IoT)-enabled FPGA controller (NodeMCU Wi-Fi module) is included to continuously monitor important metrics like motor speed, battery State-of-Charge (SoC), and panel voltage and current. A cloud-based IoT monitoring system receives this data for remote diagnostics and analytics on energy management. The validation of proposed model is done via MATLAB/Simulink, an outcomes are made compared with other classical models in terms of voltage conversion efficiency (97.1%) as well as tracking efficiency of (99.97%).

Wheat damping-off disease, primarily caused by Rhizoctonia solani (R. solani), threatens seedlings and results in significant crop losses worldwide. While chemical fungicides can harm the environment, eco-friendly options are needed. Salicylic acid and curcumin are antimicrobial, but their nanoform effectiveness against R. solani is underexplored. R. solani was isolated from diseased wheat seedlings and tested with salicylic acid, curcumin, and their nano-formulations. Fungal growth inhibition was measured at concentrations from 5 to 75 ppm, with half-maximal inhibitory concentration (IC₅₀) values calculated to assess effectiveness. The study compares the natural and nano forms of salicylic acid and curcumin in their ability to control the pathogen. Both compounds showed dose-dependent antifungal activity. At a concentration of 25 ppm, the inhibition rates of the fungus were 19.77% and 57.63% for natural curcumin and salicylic acid, respectively. At a concentration of 5 ppm, the inhibition rates of the fungus were 17.23% and 33.20% for nano-curcumin and nano-salicylic acid, respectively. The inhibitory effect increases at higher concentrations, with complete inhibition observed at 75 ppm for both compounds in their natural forms. The IC₅₀ values for salicylic acid and curcumin were 23.19 and 40.17 ppm, respectively. In comparison, the IC₅₀ values were 11.71 ppm for nano-salicylic acid and 15.71 ppm for nano-curcumin. Nanotechnology can enhance the effectiveness of natural antifungal compounds. The data reveal, for the first time, that nano-salicylic acid and nano-curcumin exhibit superior activity against R. solani compared to their conventional forms, highlighting their potential as sustainable, eco-friendly alternatives to synthetic fungicides in crop protection.

Nanomedicine offers a paradigm shift in cancer therapy due to its superior targeting capabilities, bioavailability, and versatility compared to traditional methods. Owing to their distinct physico-chemical characteristics, zinc oxide nanoparticles (ZnO-NPs) are widely explored. This research’s primary objective is to provoke apoptotic events in lung cancer cells (A549) exposed to bio-fabricated ZnO-NPs. ZnO-NPs were successfully formulated from the aqueous extract of the Jasminum sambac (L.) Aiton leaves. The phyto-fabricated JS-ZnO-NPs revealed the maximum absorbance at 327 nm in UV-spectroscopy. FT-IR analysis confirmed the functional moieties involved in aiding biosynthesis, and the components of the synthesized JS-ZnO-NPs were verified via Elemental Composition Analysis. The XRD graph revealed the crystalline features of the JS-ZnO-NPs. The semi-spherical agglomerated morphological feature with a mean grain size of 61.56 ± 3.01 nm was visualized in TEM and SEM micrographs. The surface charge was recorded at − 14 mV. The anti-cancer efficacy of JS-ZnO-NPs was proportional to their concentration, as revealed by the MTT assay, with an IC₅₀ of 44.37 µg mL⁻¹. Apoptotic profiling of JS-ZnO-NPs treated cells was carried out using AO/EtBr staining, Annexin V/PI- FACS analysis, intracellular ROS generation, DNA fragmentation, Caspase 3 activity, followed by apoptotic gene expression studies. JS-ZnO-NPs induced apoptosis in cells by triggering DNA damage, increasing oxidative stress, and activating caspase 3, amplifying the mRNA levels of the Bax and p53 genes, and downregulating the mRNA levels of the Bcl-2 gene. The outcome of this research demonstrated that JS-ZnO-NPs trigger caspase-mediated apoptosis via increased ROS generation.

This study investigates the influence of thermal treatment on the antimicrobial properties of silver nanoparticles NPs Ag⁰ deposited on a macroporous Silochrome. The research focuses on the morphological and distributional changes of the nanoparticles under elevated temperatures and their subsequent impact on antibacterial activity. The results demonstrate that increasing the treatment temperature reduces nanoparticle size and enhances their distribution on the silica surface, significantly improving antimicrobial efficacy. The immobilization of Ag⁺ cations from a solution and the incorporation of reduced NPs Ag⁰ onto the silica surface resulted in a homogeneous distribution of nanoparticles around mesopores and imparted antibacterial properties. The critical role of the acid–base centers of SiO₂ in the antibacterial activity of SiO₂/Ag⁰ nanostructures was established, and conditions for optimizing this activity were determined by altering the size and localization of NPs Ag⁰ through thermal treatment at 500 °C, which reduced the minimum inhibitory concentration by six-to-seven times. These findings highlight the potential of thermal treatment as a viable method for optimizing the antimicrobial performance of SiO₂-based nanocomposites.

This research examines the thermal behavior of Al₂O₃-based nanofluids in multilayer microchannel heat sink (MCHS) using both simulation and experimental approaches. The examinations were carried out considering three distinct nanofluid concentrations viz 0.5, 1.0, and 2.0% volume and mass flux values from 0.01 to 0.05 kg/s. Observations demonstrated that an increase in concentration enhances heat transfer performance, with Nusselt numbers ranging 112.0 at 2.0% concentration results, considering that the influence of mass flow rate on the heat dissipation coefficient rose sharply and heat transfer coefficient reached the maximum of 270.8 W/m²·K. As a consequence of it, the pressure drop that accompanied enhanced performance increased to 600 Pa in similar circumstances. This work optimizes Al₂O₃ nanofluids in multilayer MCHS, boosting heat transfer to 270.8 W/m²·K while controlling pressure drop. The optimal 1.5% concentration at 0.04 kg/s offers efficient, scalable cooling solutions for electronics, automotive, and industrial applications. This research also utilized a multi-objective optimization strategy that determined proper operating conditions that would result in both thermal efficiency and pumping power. From these findings, it is evident that Al₂O₃ nanofluids can be used in enhanced cooling applications, and researchers and engineers in the industrial and manufacturing sectors can use them in enhancing their cooling systems designs and parameters.

The increasing incidence of skin cancer, antimicrobial resistance, and oxidative stress-related conditions necessitates the development of multifunctional therapeutic agents. The main objectives of this investigation is synthesis, characterization, and biomedical assessment of silver nanoparticles (AgNPs) synthesized via a modified Turkevich method using trisodium citrate and SDS as reducing and capping agents. Characterization through ultraviolet–visible (UV–Vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, zeta potential analysis, and field-emission scanning electron microscopy (FE-SEM) confirmed the successful formation of stable, spherical AgNPs with sizes ranging from 21.99 to 41.35 nm and a moderately stable surface charge (− 27.24 mV). Biological evaluations demonstrated the dose-dependent cytotoxicity of AgNPs against A375 melanoma skin cancer cells, with significant reduction in cell viability at higher concentrations. Antibacterial assessment against Staphylococcus aureus (S. aureus) revealed strong, concentration-dependent inhibition zones, highlighting the AgNPs potential in combating resistant skin infections. Additionally, AgNPs exhibited noteworthy antioxidant activity in DPPH assays, although slightly lower than standard ascorbic acid. The results suggest that the synthesized AgNPs possess potent triple-functional activity, including anticancer, antibacterial, and antioxidant activity, supporting their applicability in integrated therapeutic strategies for skin-related conditions.

In this study, we combined experimental Piezoresponse Force Microscopy (PFM) analysis with an empirically corrected Furukawa model to predict the piezoelectric behavior of Poly(Vinylidene Fluoride-co-Trifluoroethylene) (PVDF-TrFE) films functionalized with CoFe₂O₄ (CFO) Magnetic Nanoparticles (MNPs). According to our empirical model, the piezoelectric response observed from PFM analysis on the PVDF-TrFE/CFO films was mainly influenced by the interaction between the CFO MNPs and the polymer active β phase of the polymer, providing a high piezoelectric coefficient d₃₃ (~ 6.5 pm/V) at a low CFO concentration of 5 wt%. Experimental observation of the morphological formation of the polar β domains and their phase dependence from the CFO MNPs amounts have been investigated by means of Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and Fourier Transform Infrared (FT-IR) spectroscopy analysis. Also, the local magnetic response of the PVDF-TrFE/CFO film at 5 wt% was investigated through Magnetic Force Microscopy (MFM) with a controlled magnetized tip. DC magnetic poling of the PVDF-TrFE/CFO film at 5 wt% resulted in a significant increase in the d₃₃ (~ 34 pm/V) under an applied external magnetic field of ~ 50 mT. A theoretical model of chain aggregate-like structure formation in magnetizable polymer-based nanocomposites was employed to explain the effect of CFO MNP chain unification on the local piezoelectric strain response of PVDF-TrFE/CFO films under low magnetic fields. This finding provide further insight into the implementation of flexible PVDF-TrFE/CFO thin nanocomposites with tailored piezoelectric performance, enhancing their efficiency in energy harvesting and advancing the development of next-generation piezoelectric devices.