Facile Fabrication Research Articles

Facile Fabrication of ZnO Nanorods with Extremely Strong Photocatalytic Performance and Antibacterial Activity

Development of nanomaterials with strong antibacterial action and highly enhanced photocatalytic activity for water purification is of immense interest. ZnO nanorods, with extremely enhanced solar-driven photocatalytic performance and good antibacterial activity, have been fabricated by facile chemical route. The structural properties of the nanomaterial were thoroughly characterized by SEM, TEM, EDX, HRTEM, STEM-HAADF, elemental profiling, XRD and Raman spectroscopy, while the optical and photocatalytic properties were studied by UV-vis absorption spectroscopy. TEM and FESEM showed nanorods with average width and length as 80[Formula: see text]nm and 178[Formula: see text]nm. XRD showed wurtzite ZnO with 27[Formula: see text]nm crystallite size. PL analysis of ZnO nanorods showed peaks at 415[Formula: see text]nm, 439[Formula: see text]nm, 499[Formula: see text]nm and 561[Formula: see text]nm. The fabricated ZnO nanorods exhibited extremely enhanced photocatalytic performance with very high rate constant of 0.201[Formula: see text]min[Formula: see text] for degradation of organic pollutant MB in water under only 15[Formula: see text]min of solar exposure. ZnO nanorods completely inhibited growth of Bacillus oceanisediminis and Escherichia coli at 500[Formula: see text][Formula: see text]g/mL and 700[Formula: see text][Formula: see text]g/mL, respectively. The origin of antibacterial behavior of ZnO nanorods against B. oceanisediminis and E. coli has been investigated using histidine for scavenging ROS, morphological change by SEM and agarose gel electrophoresis. Our results showed that ROS-induced oxidative stress damages cell wall, evident from SEM, and leads to fragmentation of DNA both of which contribute to the antibacterial action of ZnO nanorods. The tentative mechanism of extremely strong photodegradation performance of ZnO nanorods has also been proposed.

Versatile Gas Sensing at Room Temperature: Facile Fabrication of a PANI-PB-ZnO Hybrid Nanocomposite for Detecting Ammonia, Acetone, and Ethanol

Versatile Gas Sensing at Room Temperature: Facile Fabrication of a PANI-PB-ZnO Hybrid Nanocomposite for Detecting Ammonia, Acetone, and Ethanol

Selective determination of an ovarian cancer biomarker at low concentrations with surface imprinted nanotube based chemosensor

In this study, an electrochemical chemosensor that utilizes a conductive polymer-based molecularly imprinted polymer (MIP) surface for rapid and reliable determination of CA125 was devised. A novel method has been applied to fabricate CA125 imprinted polypyrrole nanotubes (MI-PPy NT) via vapor deposition polymerization (VDP) as a recognition element for highly selective and sensitive determination of CA125. The chemosensor was prepared by immobilizing MI-PPy NT onto screen-printed gold electrodes (Au-SPE) and the performance of the sensor was evaluated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in terms of selectivity, sensitivity, linear dynamic concentration range (LDR) and limit of detection (LOD). The MI-PPy NT@Au-SPE sensor exhibited high sensitivity (68.57 μA per decade) to the CA125 concentration ranging from 0.1 U mL−1 to 100 U mL−1 at an LOD of 0.4 U mL−1 with a correlation coefficient of 0.9922. The developed chemosensors with their novel design combined with a facile fabrication method, prove to be promising as future state-of-the-art biosensors.

Facile Fabrication of Sandalwood Oil-Based Nanoemulsion to Intensify the Fatty Acid Composition in Burned and Rough Skin.

The restoration process of burned and rough skin takes a long time and remains a critical challenge. It can be repaired through a combination of proper care, hydration, and topical therapies. In this study, a novel nanoemulsion was synthesized through the high-energy ultrasonication method. A total of five nanoemulsions (NE1-5) were prepared with varying concentrations of sandalwood oil, a nonionic surfactant (polysorbate 80), and water. Among them, NE3 had a number of appropriate physicochemical characteristics, such as physiological pH (5.58 ± 0.09), refractive index (∼1.34), electrical conductivity (115 ± 0.23 mS cm-1), and transmittance (∼96.5%), which were suitable for skin care applications. The NE3 had a strong surface potential of -18.5 ± 0.15 mV and a hydrodynamic size of 61.99 ± 0.22 nm with a polydispersity index of 0.204. The structural integrity and a distinct droplet size range between 50 and 100 nm were confirmed by transmission electron microscopic analysis. The skin regeneration and restoration abilities of synthesized nanoemulsions were examined by conducting an in vivo study on Sprague-Dawley rats. Exposure to NE3 significantly increased the healing process in burned skin as compared to untreated control and nonemulsified sandalwood oil. In another set of experiments, the NE3-treated rough skin became softer, smoother, and less scaly than all other treatments. Enhanced fatty acids, i.e., palmitic acid, stearic acid, and cholesterol, were recorded in NE3-supplemented burned and rough skin compared to the untreated control. The NE3 had outstanding compatibility with key components of skincare products without any stability issues. Its biocompatibility with the cellular system was established by the negligible generation of reactive oxygen species (ROS) and a lack of genotoxicity. Considering these results, NE3 can be used in cosmetic products such as creams, lotions, and serums, allowing industries to achieve improved product formulations and provide better healthcare benefits to humanity.

Reprogrammable Magnetic Soft Actuators with Microfluidic Functional Modules via Pixel-Assembly.

Magnetic soft actuators and robots have attracted considerable attention in biomedical applications due to their speedy response, programmability, and biocompatibility. Despite recent advancements, the fabrication process of magnetic actuators and the reprogramming approach of their magnetization profiles continue to pose challenges. Here, a facile fabrication strategy is reported based on arrangements and distributions of reusable magnetic pixels on silicone substrates, allowing for various magnetic actuators with customizable architectures, arbitrary magnetization profiles, and integration of microfluidic technology. This approach enables intricate configurations with decent deformability and programmability, as well as biomimetic movements involving grasping, swimming, and wriggling in response to magnetic actuation. Moreover, microfluidic functional modules are integrated for various purposes, such as on/off valve control, curvature adjustment, fluid mixing, dynamic microfluidic architecture, and liquid delivery robot. The proposed method fulfills the requirements of low-cost, rapid, and simplified preparation of magnetic actuators, since it eliminates the need to sustain pre-defined deformations during the magnetization process or to employ laser heating or other stimulation for reprogramming the magnetization profile. Consequently, it is envisioned that magnetic actuators fabricated via pixel-assembly will have broad prospects in microfluidics and biomedical applications.

Mask-inspired moisture-transmitting and durable thermochromic perovskite smart windows

Thermochromic perovskite smart windows (TPWs) are a cutting-edge energy-efficient window technology. However, like most perovskite-based devices, humidity-related degradation limits their widespread application. Herein, inspired by the structure of medical masks, a unique triple-layer thermochromic perovskite window (MTPW) that enable sufficient water vapor transmission to trigger the thermochromism but effectively repel detrimental water and moisture to extend its lifespan is developed. The MTPW demonstrates superhydrophobicity and maintains a solar modulation ability above 20% during a 45-day aging test, with a decay rate 37 times lower than that of a pristine TPW. It can also immobilize lead ions and significantly reduce lead leakage by 66 times. Furthermore, a significant haze reduction from 90% to 30% is achieved, overcoming the blurriness problem of TPWs. Benefiting from the improved optical performance, extended lifespan, suppressed lead leakage, and facile fabrication, the MTPW pushes forward the wide applications of smart windows in green buildings.

Co1.22xNixO4/fMWCNTs-hybrid nanocomposite-based self-adhesive wearable non-enzymatic electrochemical sensor for continuous glucose monitoring in sweat

The development of polymer-based wearable, eco-friendly, and non-invasive sensors has been boosted by the rapid emergence and evolution of soft electronics. However, challenges in the catalysis of glucose and sweat sampling have hampered these advances in the development of efficient wearable glucose sensors. Herein, the porous Co1.22xNixO4 hybrid composite material with interconnecting fMWCNTs, referred to as Co1.22xNixO4/fMWCNTs, was hydrothermally synthesized, and covalently crosslinked into well-patterned, flexible PDMS polymer networks. The hydrophilic fMWCNTs enhanced the anchoring spots for the in situ growth of NiCo–Oxides, which significantly improved the conductive networks and introduced many interface zones with high sensitivity of (1190.9 and 1312.1) µA·mM−1·cm−2, wide linear range of (0.001 − 8.0) mM, low detection limit (20 μM), good long-term stability, and excellent selectivity in alkaline solution. A prototype sensor was fabricated by assembling transparent PDMS film with a hydrophilic membrane of supramolecular double network hydrogel (SP−DN) as adhesive, and breathable substrate for sweat collection. The sensitivity of the calibrated prototype was found to be 1326.83 µA·mM−1·cm−2 with a linear range of ≤ 800 µM, tested in artificial sweat samples. The feasibility of a non-invasive glucose sensor was validated by assembling and testing prototype sensors on multiple volunteers. The SP−DN hydrogel acts as a continuous OH− ion supplier, and makes it possible to oxidize the glucose by metal-oxide-based nano-enzyme. The facile fabrication method and reliability of the results with real blood samples show the potential of the metal-oxide-based sensor prototype as a flexible, and environment-adaptable sensing device.

Novel Materials and Processes for Miniaturization in Semiconductor Packaging

The semiconductor industry is undergoing a significant transformation away from conventional methods of shrinking devices and reducing costs. Chip designers are actively exploring new technological avenues to improve cost-effectiveness while integrating more features into the silicon footprint. One promising strategy is Heterogeneous Integration (HI), which employs advanced packaging techniques to integrate independently designed and manufactured components using the most suitable process technology. However, the adoption of HI brings about design and security challenges. To facilitate HI, it is crucial to advance research and development in advanced packaging.The existing research highlights potential security threats in the advanced packaging supply chain, particularly due to the offshore presence of most Outsourced Semiconductor Assembly and Test (OSAT) facilities/vendors. Addressing the growing demand for semiconductors and ensuring a secure semiconductor supply chain have prompted significant efforts from the United States (US) government to relocate semiconductor fabrication facilities onshore. However, enhancing US-based advanced packaging capabilities is essential to fully realize the vision of establishing a secure, efficient, and resilient semiconductor supply chain. Our endeavor was driven by the need to identify potential bottlenecks and vulnerabilities in the US-based advanced packaging supply chain.

Novel Materials and Processes for Miniaturization in Semiconductor Packaging

The semiconductor industry is undergoing a significant transformation away from conventional methods of shrinking devices and reducing costs. Chip designers are actively exploring new technological avenues to improve cost-effectiveness while integrating more features into the silicon footprint. One promising strategy is Heterogeneous Integration (HI), which employs advanced packaging techniques to integrate independently designed and manufactured components using the most suitable process technology. However, the adoption of HI brings about design and security challenges. To facilitate HI, it is crucial to advance research and development in advanced packaging.The existing research highlights potential security threats in the advanced packaging supply chain, particularly due to the offshore presence of most Outsourced Semiconductor Assembly and Test (OSAT) facilities/vendors. Addressing the growing demand for semiconductors and ensuring a secure semiconductor supply chain have prompted significant efforts from the United States (US) government to relocate semiconductor fabrication facilities onshore. However, enhancing US-based advanced packaging capabilities is essential to fully realize the vision of establishing a secure, efficient, and resilient semiconductor supply chain. Our endeavor was driven by the need to identify potential bottlenecks and vulnerabilities in the US-based advanced packaging supply chain.

Facile fabrication of superhydrophobic and antibacterial dual-functional cotton fabrics for oil–water separation

Facile fabrication of superhydrophobic and antibacterial dual-functional cotton fabrics for oil–water separation

Highly efficient OLED achieved by periodic corrugations using facile fabrication

In this study, a newly facile method for fabricating corrugations as light extractor in OLED was developed. The corrugated structure fabricated using simple polymer molding and ultraviolet (UV) forming was identified to feature high transmittance of 87.5 % and a haze of 38.5 % in UV–vis wavelength range, respectively, promoting the light extraction. Consequently, compared with planar OLED, corrugated OLED with period of 417 nm was found to exhibit a significant increase in external quantum efficiency (ηEQE), rising from 25.5 % to 34.0 %, while maintaining identical electrical characteristics. In addition, attaching a macro-lens to further improve the ηEQE by an impressive 52.6 %. Overall, a remarkable enhancement of 106.2 % was achieved through internal corrugation combined with an external lens, which can be attributed to the reduction of total internal reflection in waveguide and substrate modes, along with minimized light loss in surface plasmon polariton mode. These findings highlight the potential of periodic corrugated structures in realizing efficient OLEDs for lighting or next generation displays.

Flexible Embedded Metal Meshes by Sputter-Free Crack Lithography for Transparent Electrodes and Electromagnetic Interference Shielding.

A facile and novel fabrication method is demonstrated for creating flexible poly(ethylene terephthalate) (PET)-embedded silver meshes using crack lithography, reactive ion etching (RIE), and reactive silver ink. The crack width and spacing in a waterborne acrylic emulsion polymer are controlled by the thickness of the polymer and the applied stress due to heating and evaporation. Our innovative fabrication technique eliminates the need for sputtering and ensures stronger adhesion of the metal meshes to the PET substrate. Crack trench depths over 5 μm and line widths under 5 μm have been achieved. As a transparent electrode, our flexible embedded Ag meshes exhibit a visible transmission of 91.3% and sheet resistance of 0.54 Ω/sq as well as 93.7% and 1.4 Ω/sq. This performance corresponds to figures of merit (σDC/σOP) of 7500 and 4070, respectively. For transparent electromagnetic interference (EMI) shielding, the metal meshes achieve a shielding efficiency (SE) of 42 dB with 91.3% visible transmission and an EMI SE of 37.4 dB with 93.7% visible transmission. We demonstrate the highest transparent electrode performance of crack lithography approaches in the literature and the highest flexible transparent EMI shielding performance of all fabrication approaches in the literature. These metal meshes may have applications in transparent electrodes, EMI shielding, solar cells, and organic light-emitting diodes.

Facile fabrication and biological investigations of metal oxides intercalated in kaolinite clay-based dressing material to improve wound healing ability in nursing care after post-operative period

The present investigation aims to design and development of hybrid zinc oxide (ZnO) and manganese dioxide (MnO2) nanoparticles (NPs) doped-biopolymer matrix-based cost-effective technique for the synthesis of biocompatible Kaolinite/Chitosan (Ka/CS) nanocomposites (NCs) could be used as agents for wound healing due to their efficiency and low toxicity. The crystallite size, phase purity and surface morphology of the synthesised NCs were investigated systemic analytical methods. The results revealed that the metal oxide nanocomposites presented that in rod-crystalline in shape and additionally exhibits that 20–30 nm in size. In vitro antibacterial analyses demonstrates that NCs have significantly improved bactericidal inhibition efficiency when compared to the bare hybrid NPs and polymeric components. The in vitro biocompatibility observation demonstrates that prepared hybrid-NPs encapsulated NCs have enhanced cell survival rate (>90 %), which was established by MTT assay and Live/Dead fluorescence assay methods at different incubation time. The DPPH assay was used to investigate the synergistic effects of prepared dressing materials increased antioxidant activity. Preliminary research indicates that these nanocomposites, ZnO/MnO2 incorporated and decorated with Ka/CS NCs, could be a significant promoter and potential candidate for use as a robust wound healing agent in post-operative nursing care.

Nanopore Fabrication Made Easy: A Portable, Affordable Microcontroller-Assisted Approach for Tailored Pore Formation via Controlled Breakdown.

With growing interest in solid-state nanopore sensing─a single-molecule technique capable of profiling a host of analyte classes─establishing facile and scalable approaches for fabricating molecular-size pores is becoming increasingly important. The introduction of nanopore fabrication by controlled breakdown (CBD) has transformed the economics and accessibility of nanopore fabrication. Here, we introduce the design of an Arduino-based, portable USB-powered CBD device, with an estimated cost of <150 USD, which is ≈10-100× cheaper than most commercial solutions, capable of fabricating single nanopores conducive for single molecule sensing experiments. We demonstrate the facile fabrication of 60 tailored nanopores (∼2.6-12.6 nm) with ∼80% of the pores within 1 nm of the target diameter. Selected pores were then tested with double-stranded DNA, the canonical molecular ruler, demonstrating their performance for single-molecule sensing applications. The device is constructed with off-the-shelf readily available components and controlled using a highly customizable MATLAB application, which has capabilities encompassing pore fabrication, pore enlargement, and current-voltage acquisition for pore size estimation. When combined with a portable amplifier, this device also provides a fully portable sensing platform, an important step toward portable solid-state nanopore sensing applications.

Metal organic framework-loaded biohybrid magnetic microrobots for enhanced antibacterial treatment

Overused antibiotics has caused a serious threat of pathogen resistance, and it is urgent to develop drug-free strategies for efficient bacterial eradication. Metal organic frameworks (MOFs) can gradually release metal ions to kill bacteria, yet it is challenging for them to achieve good dispersion and targeted mobility with enhanced antibacterial efficiency. Herein, we developed ZIF-8 loaded biohybrid magnetic microrobots using chlorella cells as biotemplates for the first time, and demonstrated their excellent antibacterial performance. In this approach, Fe3O4 nanoparticles were deposited inside chlorella, which were further coated with a compact layer of ZIF-8 nanoparticles. The as-prepared microrobots could be flexibly actuated with high velocity under magnetic actuation. Besides, a series of antibacterial tests were conducted to verify that Zn2+ was efficiently released from the ZIF-8 shell for bacterial inhibition, which could also be significantly enhanced via controlled magnetic propulsion. Due to their facile fabrication and remarkable versatility, MOF-loaded microrobots hold great potential for the active treatment of bacterial infections.

Facile green fabrication of copper/polyvinylidene fluoride nanocomposite for pathogens disinfection and dye degradation in wastewater

This study aimed to explore the production of valuable nanomaterials using natural waste-derived extracts through a green synthesis approach. Copper nanoparticles (CuNPs) were successfully fabricated using coffee grounds as a reducing agent. Characterization via TEM and DLS confirmed the small average size of the biogenic CuNPs, while XRD analysis indicated their formation in a pure state without impurities. To enhance effectiveness in bacterial disinfection, dye degradation, and conductivity, a CuNPs@polyvinylidene fluoride (PVDF) nanocomposite was developed. Various spectroscopic and microscopic methods validated CuNPs production. Experimental data demonstrated significant antibacterial activity in the CuNPs@PVDF nanocomposite, eliminating harmful bacteria (Salmonella enterica, Klebsiella pneumoniae, Bacillus subtilis, and Enterococcus faecalis) within 60 to 115 min. At concentrations of 50, 100, and 150 µg/mL, the nanocomposite notably accelerated Methyl Red (MR) dye degradation, achieving degradation rates of 68.72 %, 81.48 %, and 100 % after 150 min. These findings advocate for the potential use of the CuNPs@PVDF nanocomposite in eliminating pathogens and reducing organic dye pollution. Its eco-friendly synthesis, effective disinfection, and photocatalytic proficiency signify its wide applicability in water treatment, establishing it as a promising solution for tackling water contamination issues.

Porous Microneedles Through Direct Ink Drawing with Nanocomposite Inks for Transdermal Collection of Interstitial Fluid.

Interstitial fluid (ISF) is an attractive alternative to regular blood sampling for health checks and disease diagnosis. Porous microneedles (MNs) are well suited for collecting ISF in a minimally invasive manner. However, traditional methods of molding MNs from microfabricated templates involve prohibitive fabrication costs and fixed designs. To overcome these limitations, this study presents a facile and economical additive manufacturing approach to create porous MNs. Compared to traditional layerwise build sequences, direct ink drawing with nanocomposite inks can define sharp MNs with tailored shapes and achieve vastly improved fabrication efficiency. The key to this fabrication strategy is the yield-stress fluid ink that is easily formulated by dispersing silica nanoparticles into the cellulose acetate polymer solution. As-printed MNs are solidified into interconnected porous microstructure inside a coagulation bath of deionized water. The resulting MNs exhibit high mechanical strength and high porosity. This approach also allows porous MNs to be easily integrated on various substrates. In particular, MNs on filter paper substrates are highly flexible to rapidly collect ISF on non-flat skin sites. The extracted ISF is used for quantitative analysis of biomarkers, including glucose, = calcium ions, and calcium ions. Overall, the developments allow facile fabrication of porous MNs for transdermal diagnosis and therapy.

Facile fabrication of fluorine-free waterproof and breathable nanofiber membranes with UV-resistant and acid-alkali resistant performances

Membranes with good waterproofness and breathability are desired for the preparation of outdoor sports garments. However, current waterproof and breathable membranes use environmentally hazardous fluorine-containing raw materials and suffer from many problems such as complicated preparation processes and single function. Therefore, it is a great challenge to select environmentally friendly raw materials to prepare multi-functional membranes with waterproof-breathable performance by simple preparation method. In this paper, fluorine-free poly(styrene-b-butadiene-b-styrene) (SBS), polyurethane (PU), and 2-hydroxy-4-n-octyloxy benzophenone (UV531) were selected to prepare multi-functional nanofiber membranes by convenient one-step electrospinning. The properties of the environmentally friendly multi-functional SBS/PU/UV531 nanofiber membranes were systematically optimized by adjusting the concentration of UV531 in the nanofiber membranes. The ultimately obtained multi-functional SBS/PU/UV531–2 nanofiber membrane shows excellent waterproofness (hydrostatic pressure: 58.8 kPa), high breathability (WVT rate: 5.2 kg m−2 d−1), good mechanical properties (breaking strength: 7.26 MPa, breaking elongation: 327.9%), excellent UV resistance (UPF: 238.23), and strong acid and alkali resistance properties. This multi-functional nanofiber membrane has broad application prospects in a variety of fields such as outdoor protective clothing, extreme environment materials, and military products.

Capillary-Assisted Assembly of Soft Conductive Polymer Nanopillar/Tube Arrays and Applications.

Nanopillar/tube arrays have emerged as encouraging platforms, possessing remarkable advantages, including large specific areas and highly aligned orientations. Despite the progress of nano/microfabrication technologies, facile and controllable fabrication of conductive polymer nanopillar/tube arrays remains challenging. In this study, we demonstrate that the air-liquid interfacial self-assembly can be extended to obtain three-dimensional nanostructured arrays. A smart and novel method is proposed for preparing uniform conductive polymer nanopillar/tube arrays by a template-mediated interfacial synthesis approach. By utilizing capillary force, precise control processes of the nanostructure and patterned structure can be easily realized. Furthermore, a transfer strategy is devised, allowing for scalable fabrication and expansion of the applicability. Applications, including antibacterial surfaces and actuators, have been demonstrated. We extend the air-liquid interfacial synthesis technique as a powerful and universal strategy for producing ordered nanopillar/tube arrays and show the great potential of soft nanostructured arrays as advanced platforms in diverse applications.

Metal-organic-framework-derived boron and nitrogen dual-doped hollow mesoporous carbon for photo-thermal catalytic conversion of CO2

The facile fabrication of hollow materials with rich defects is highly desired for photothermal conversion of CO2. Herein, we successfully prepared Zn, B, and N co-doped hollow mesoporous carbon (BHNC) by directly pyrolyzing phenylboronic acid/melamine/ZIF-8. The hollow porous structure of the resulting BHNC material can not only achieve high photothermal conversion efficiency but also effectively promote substrate mass transfer. Moreover, the introduction of B extends the light absorption scope of the material, offers active sites for chemical adsorption and further activation of CO2, significantly promoting the cycloaddition reaction. Benefiting from their high specific surface area, hollow mesoporous nanoarchitecture and rich defects, the optimized BHNC can be employed as a high-efficiency catalyst for the CO2 cycloaddition reaction under light irradiation and ambient conditions, affording 3 times higher yield of 4-(chloromethyl)-1,3-dioxolan-2-one (97%) than that of ZIF-8-800. This study provides a new strategy for the design of efficient catalysts for CO2 conversion under mild conditions.