Nanoscale Research Letters最新文献

In this study, a comprehensive process–structure–function roadmap was established for bio-inspired functional surfaces. We systematically controlled the pore diameter, interpore distance, pore depth, and pore aspect ratio of anodic aluminum oxide (AAO) master templates via multistep anodization. These templates were then replicated in durable nickel–cobalt alloy working molds through electroforming, and their nanostructures were transferred to polycarbonate films using nanoimprint lithography. Our findings highlighted the critical influence of pre-anodization, electrolyte type (oxalic acid for an ~ 100 nm interpore distance; phosphoric acid for ~ 400 nm), anodization potential, and time on the AAO structures. We also identified 100 A/m² as the optimal current density for achieving high-aspect-ratio structures under intense anodization. The polymer film replicas obtained using these precisely controlled templates showed significantly enhanced functional properties: the average surface reflectance decreased from 10.85% to a minimum of 3.5%, transmittance increased from 80.1 to 92.3%, and water contact angles improved from 91.46 to 138.69°. Thus, a higher structural aspect ratio is crucial for enhanced hydrophobic performance, consistent with the Cassie–Baxter model. In summary, this research provides an efficient, controllable method for manufacturing high-performance bio-inspired functional surfaces and, more critically, establishes direct correlations between anodization parameters and the resulting optical and wetting properties, offering key guidance for material design.

Aedes aegypti is a primary vector of arboviral diseases, including chikungunya, dengue fever, yellow fever, and Zika virus. Given the increasing global burden and the limitations of synthetic repellents, there is a growing need for safe and effective botanical alternatives, especially in endemic regions. This study formulated thymol-, carvacrol-, and cinnamaldehyde-loaded nanoemulsions via spontaneous emulsification and subsequently gelled using hydroxypropyl methylcellulose (HPMC). Viscosity and encapsulation efficiency were assessed using viscometry and Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The repellent efficacy of the resulting nanogels against Ae. aegypti was assessed and benchmarked against DEET (40% w/v). The nanoemulsions exhibited particle sizes of 208 ± 5 nm, 183 ± 6 nm, and 193 ± 4 nm for thymol, carvacrol, and cinnamaldehyde, respectively. Among all formulations, carvacrol-based nanogel (3% w/v) demonstrated the longest protection time (250 ± 34 min), exceeding the commercial DEET formulation (190 ± 17 min). These findings highlight the potential of HPMC-based nanogel repellents, particularly those containing carvacrol, as effective and safer botanical alternatives to conventional repellents, with promising implications for integrated vector management strategies.

This article explores the phyto-synthesis of silver nanoparticles (Ag NPs) derived from the floral extract of Punica granatum and their potential applications in antibacterial and anticancer treatments. In the synthesis process, silver nitrate (AgNO₃) has been utilized as both a reducing and stabilizing agent, leading to the successful formation of stable silver nanoparticles (PG-Ag NPs). The nanoparticles were characterized using various analytical techniques, revealing their spherical shape and uniform dispersion, with an average size of ~ 27 (± 2) nm. The antibacterial and anticancer properties of the PG-AgNPs have been investigated, demonstrating significant anticancer activity with an IC₅₀ value of ~ 13 µg/mL. Furthermore, the nanoparticles exhibited potent antimicrobial efficacy against Escherichia coli and Staphylococcus aureus. These findings indicate that PG-Ag NPs, synthesized from Punica granatum flower extract, present a promising and cost-effective solution for antibacterial and anticancer applications.

The application of anticorrosion composite coating is a successful strategy for preventing metal corrosiveness. Application of Nanoparticles as Corrosion inhibitors effectively prevents the corrosion of metals compared to existing corrosion inhibitors. Conventional corrosion inhibitors are toxic to the environment. Following exploitation, the epoxy coatings on the steel erode as well. Nanoparticles are therefore introduced to prevent it. In this paper, NiZn₂O₄ Nanoparticles are synthesized by polymeric precursor method using alginic acid. Epoxy resin is infused with the synthesised nano NiZn₂O₄ to prevent mild steel from corroding. Nano NiO and ZnO has a high corrosion resistance. Hence NiZn₂O₄ was prepared which will have a synergistic effect thereby preventing oxidation and environment friendly. To examine its efficiency different concentrations of (1%,3%,5%) of NiZn₂O₄ nanoparticles were added to epoxy coating and applied on mild steel in 1.0 M HCl solutions. Using potentiodynamic polarisation and gravimetric (weight loss) techniques, the corrosion inhibiton efficiency was examined. A gravimetric investigation was carried out within 15 days of exposure, and the findings indicated that weight loss increase with exposure duration but diminished with higher NiZn₂O₄NP concentration. Additionally, the presence of NiZn₂O₄NPs altered the process of anodic dissolution and cathodic hydrogen gas evolution, according to potentiodynamic polarisation data from electrochemical impedance spectroscopy. From the results we observed that 3% loading of NiZn₂O₄ Nanoparticle coating was efficient with high corrosion resistance (Low corrosion rate 0.0107). These findings showed that NiZn₂O₄NPs might be added to the current inhibitors to reduce the rate of corrosion.

Hybrid organic-inorganic perovskites, with power conversion efficiencies comparable to those of polycrystalline silicon-based counterparts, as well as tunable band gaps and low-temperature solution processability, represent a promising class of optoelectronic semiconductors suitable for next-generation electronics. In this work, we synthesised high-quality single-crystal and thin films of methylammonium bismuth iodide (MBI) using an antisolvent assisted method. The X-ray diffraction analysis showed a hexagonal crystal structure for the synthesised MBI crystal with space group P6₃/mmc. The bandgap of the MBI film estimated from the absorption spectra is 2.19 eV. The thermogravimetric analysis indicates that the thermal stability of MBI exceeds that of its constituents, thereby offering improved thermal stability. Furthermore, a trap state density comparable to that of vacuum processed condition is achieved by antisolvent treatment. The impedance and dielectric characteristics of MBI are recorded for a frequency range of 100 Hz to 1 MHz and the complex impedance is analysed by fitting the Nyquist plot. A mobility of 2.29 × 10^− 6 cm² V^− 1 s^− 1 is deduced by fitting the space charge limited current (SCLC) region, and a photovoltaic analysis was performed using MBI as an absorber.

This study investigated the impact of pixel size and inter-pixel gap width on the optoelectronic performance of micro-LED arrays, with a particular focus on their application in visible light communication (VLC). Boron ion implantation was employed to define pixel emission areas and achieve effective channel insulation due to boron’s small atomic radius and its ability to suppress electrical conductivity in implanted regions without significantly degrading the optical performance. The micro-LED arrays, with a total emitting area of 14,400 μm², incorporated pixel sizes of 5 μm, 8 μm, and 10 μm, alongside gap widths of 2 μm, 4 μm, 6 μm, and 8 μm. The experimental results demonstrated a consistent increase in light output power and external quantum efficiency (EQE) with decreasing gap widths, which is attributed to reduced leakage currents and minimized non-radiative recombination losses. The small size of boron ions allowed for precise electrical isolation between pixels without affecting emission properties, enabling accurate evaluation of size-dependent performance. In VLC applications, pixel size and gap width not only influenced light output power and EQE but also impacted bandwidth, full-width at half-maximum, and data transmission rates. The 12 × 12 array with a 10 μm pixel size achieved the best VLC performance, with a bandwidth of 171.88 MHz at a current density of 347.2 A/cm².

Carbon nanotube field effect transistor (CNTFET) based multivalued logic (MVL) circuits capable of delivering high computational efficiency are required in contemporary digital systems for resolving data transfer issues. Quaternary logic can lead to the reduction of interconnections, as more information can be transferred by using four logic levels in high-speed and high-density. This work proposes novel standard quaternary inverter, SQNAND and SQNOR logic gates based on the stacking technique. These novel gates have been used in the design of a quaternary half adder. The simulation results for proposed quaternary circuits have been obtained using HSPICE with the 32 nm CNTFET Stanford model. The proposed designs of SQI, SQNAND, and SQNOR circuits are operated at a supply voltage of 0.9 V and show power delay product (PDP) of 0.776, 1.523, and 2.746 aJ, respectively. The area consumed by SQI, SQNAND, and SQNOR circuits is 7636, 16,456, 16,864 λ², respectively. Further, the power consumption and PDP for the proposed QHA are 1.01 µW and 0.806 10^–16 J, respectively. The proposed QHA shows improvement in PDP in contrast to other QHA designs reported earlier and is anticipated to be used for futuristic computing systems.

The emerging paradigm of cell-to-cell communication represents a transformative shift from device-mediated contact to bio-integrated, emotion-driven interactions. This article introduces a novel, multi-layered framework for enabling biologically integrated communication between cells, devices, and computational systems using the paradigm of Molecular Communication (MC). Moving beyond traditional digital interfaces, the proposed architecture, comprising in-body, on-chip, and external communication layers, models and processes intercellular signaling via molecular emissions, implantable biosensors, and nano-electronic processors. Theoretical foundations are extended to fractional-order diffusion systems and neuromorphic decoding, capturing complex behaviors in realistic biological environments. We further propose a cross-layer molecular digital twin model for context-aware interpretation and feedback. The framework’s applications are grounded in the molecular underpinnings of emotion, where neurotransmitters like oxytocin and serotonin mediate prosocial behaviors and affective states through cell-to-cell signaling. For instance, remote emotional interfacing leverages MC to modulate oxytocin release, mimicking natural empathy circuits, while consensual telepathy draws from BCI-mediated neural pattern sharing, extending molecular-level decoding to cognitive-emotional relays. These are not mere metaphors but extensions of established neurochemical pathways, as evidenced by recent studies showing serotonin fluctuations amplify context-specific emotions. This work thus bridges cellular mechanisms to higher-order phenomena, ensuring scientific rigor in bio-digital systems .

The Ni-doped oxide electrodes were prepared by the span-60 sol–gel route for the electrochemical formation of oxygen in an alkaline medium. The prepared oxides were characterized physicochemically by the FTIR, P-XRD, and SEM techniques to study their formation, structure, and morphology. The prepared oxide electrodes were tested for their electrochemical performance for oxygen evolution reaction by the cyclic voltammetry and the Tafel polarization techniques. The voltammograms of each oxide electrode showed two redox peaks, one cathodic peak (E_pa = 170–245 mV) and another anodic peak (E_pa = 541–603 mV). The electrocatalytic performance of oxide electrodes in 1 M KOH at 25°C was investigated using the Tafel polarization method. Doping nickel in the oxide matrix greatly enhanced the electrocatalytic activity for the oxygen evolution reaction (OER). The most active electrode in the current study was the 0.8-mol nickel substituted oxide electrode, which demonstrated a Tafel slope (b) of 88 mVdec⁻¹ and a current density (j) of 50 mA cm⁻² at 331 mV oxygen over potential. It followed a first-order reaction mechanism regarding the change in [OH⁻] concentration. The temperature-dependent kinetics of the oxide electrode were also investigated at various temperatures, revealing thermodynamic characteristics including the standard entropy of reaction ((Delta {S}_{el}^{0ne })) for the OER ranging from 232 to 303 J deg⁻¹ mol⁻¹ and the standard electrochemical activation energy (Ea) ranging from 10 to 30 kJ mol⁻¹. A high negative reaction entropy value indicates that the adsorption of reaction intermediate species at the surface electrode is the mechanism by which OER takes place.

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