Journal of Science: Advanced Materials and Devices最新文献

In order to create alloys with exceptional properties for orthopedic uses, this study focuses on the impact of zirconium (Zr) content on the structural, electrochemical, and tribological qualities of nanostructured Ti–25Nb-xZr [x = 5, 10, 15, 20, 25, and 30 atomic (at.) %] alloys. The structural evolution was investigated using XRD and SEM techniques. The mechanical characteristics of the produced alloys, including Vickers hardness and Young's modulus, were measured. In addition, the corrosion tests were performed using the OCP, EIS, and PD methods in Ringer's solution within the independent pH range at 37 °C. A ball-on-disc tribometer was used to investigate the tribological behavior of the alloys under various loads and wet conditions using the Ringer solution. It has been verified that Zr content (at. %) in the alloys had an impact on their morphologies, structural evolution, and mechanical characteristics. According to the morphological analysis, the particle and crystallite size decreases with increasing Zr content. Young's modulus and Vickers hardness show the same tendency. The EIS data demonstrated that a single passive film formed on the alloy surfaces, and the addition of Zr enhanced the corrosion resistance of the passive films. The polarization curves demonstrate that the alloys had low corrosion current densities and large passive areas without the passive films disintegrating. Likewise, the inclusion of Zr resulted in a reduction in the corrosion and passive current density values. All of these results suggested that the titanium alloys exhibit a more noble electrochemical activity caused by Zr. From the tribological perspective, it was found that the friction coefficient of the alloys reduced with increasing Zr content.

Tungsten (W) is the most promising material for future plasma-facing materials. Its alloys or composites reinforced with various compounds have been studied to improve the irradiation resistance of W. This study aimed to investigate the effect of boron-containing reinforcement in the W matrix against He⁺ ion irradiation. Cerium hexaboride (CeB₆) particulates, which have high neutron shielding properties, were incorporated into the W matrix pre-alloyed by 1 wt% Ni (W1Ni). CeB₆ powders were home-made and prepared from CeO₂/Mg/B₂O₃ powder blends via mechanochemical synthesis and purification steps. 1, 5, and 10 wt% CeB₆ powders were added to pre-alloyed W1Ni by mechanical alloying, and then they were consolidated by using pressureless sintering (PS, 1400 °C, 1 h) and spark plasma sintering (SPS, 1410 °C, 1 min) techniques. CeB₆ particle-reinforced W1Ni composites contained different amounts of reinforcements were prepared by two different sintering methods and were compared with respect to their compositional, microstructural, and microhardness properties and wear and irradiation behaviors. Based on the results, increasing the CeB₆ reinforcement amount in the composite triggered the formation of the W₂B phase, especially in the W1Ni–10CeB₆ composite after both sintering methods. The mechanical and irradiation properties were enhanced more by increasing the CeB₆ amount in the case of using the SPS method. When compared to other sintered samples, the SPS'ed W1Ni–10CeB₆ composite has the lowest specific wear rate of ∼4 × 10⁻⁷ mm³/Nm and the maximum hardness value of ∼21 GPa. According to surface deformation, the W1Ni–5CeB₆ composite exhibited comparatively higher resistance to He⁺ ion irradiation.

Mitigating the global warming caused by CO₂ emissions from anthropogenic sources is a hot research topic in the current era. The high cost and difficulty in handling liquid solvent absorbents for CO₂ capture are the main barriers to their industrial application. Earth-abundant solid sorbents are favorable candidates for CO₂ separation, offering a low energy penalty for CO₂ desorption. Here, Polysulfone (PSF) nanocomposites were prepared by simple solution blending. The carbon-based fillers, namely carbon nanotubes (CNT), and activated carbon (CA) in the range of 5–20 wt%, containing iron nanoparticles, were used as fillers. Their morphological, thermal, CO₂ capture capacity and magnetic properties were comprehensively studied. Transmission electron microscopy (TEM) evidenced uniform filler distribution in the polymer matrix with sizes of 47–54 nm. Thermal analysis revealed an approximately 4 °C improvement in both the initial (T_onset) and maximum (T_max) degradation temperatures by adding 5 wt% of nanoparticles compared to the pristine polymer. The glass transition temperature (T_g) of the pristine PSF and produced nanocomposites showed identical values as estimated by differential scanning calorimetry (DSC). The increase in filler amount gradually decreased the water contact angle values, indicating a hydrophilic classification of the PSF nanocomposites. The obtained PSF nanocomposites exhibited an efficient CO₂ capture capacity of about 40–61 mgCO₂/g at 45 °C, higher than pristine PSF. This remarkable achievement sets a new benchmark compared to previously developed systems. The introduction of the filler transforms the diamagnetic polymer matrix into a ferromagnet, presenting a coercivity of about 480 Oe, enhancing the material's potential for applications in microelectronics.

This research introduces a novel approach to repurposing walnut shells, an abundant agricultural waste, to synthesize sustainable nitrogen-doped activated carbon (N@AC). The resulting material exhibits remarkable properties suitable for dual applications in high-performance all-solid-state supercapacitors and efficient Rhodamine B dye (RhB) adsorption. In a three-electrode setup, the N@AC electrode exhibits an impressive specific capacitance of 484.6 Fg⁻¹ at 1 Ag⁻¹ and remarkable long-term stability, maintaining 97.4% of its initial performance even after 5000 charge-discharge cycles. Simultaneously, the all-solid-state symmetric supercapacitor configuration (N@AC//N@AC) demonstrates outstanding specific capacitance, registering at 168.8 Fg⁻¹ at 1 Ag⁻¹, accompanied by a favourable rate capability of 67.3% at 10 Ag⁻¹. Notably, the N@AC//N@AC configuration attains a high energy density of 39.8 WhKg⁻¹ at 1 Ag⁻¹. Furthermore, N@AC//N@AC exhibits favourable cyclic stability, retaining 83.91% of its initial capacitance even after 10,000 charge-discharge cycles. Moreover, the adsorption efficiency of N@AC toward RhB is scrutinized, highlighting its efficacy in addressing environmental remediation challenges. The porous architecture and nitrogen functionalities of N@AC play a crucial role in expeditiously eliminating organic pollutants from aqueous solutions, offering a sustainable approach to treating wastewater. Optimal conditions for the highest RhB adsorption are identified: pH 7.2, a contact duration of 180 min, and an initial dye concentration of 20 mgL⁻¹. Thermodynamic evaluations, encompassing the determination of ΔH^◦, ΔH^◦, and ΔS^◦, signify the endothermic and spontaneous nature of the adsorption process. In desorption investigations, it is noted that H₂O, employed as an eluting agent, proficiently releases 87.35% of the adsorbed RhB dye.

Employing electric double-layer (EDL) capacitors to harvest low-grade heat (LGH) is a novel technique in the high-efficiency energy absorption field. This work reports the fabrication of a vertical thermoelectric cell, based on a nanoporous graphene electrode immersed in low-concentration saline solution, for use as thermo-charging supercapacitors to convert LGH to electricity via thermally induced voltage. Because of a large specific area and a large number of micropores of nanoporous graphene films, the effective thermoelectric coefficient of the thermoelectric cell containing 0.01 M KCl solution can reach as high as 4.73 mV/°C. However, many factors, such as electrode materials, electrolyte solutions, and energy conversion device components, determine the efficiency of a thermoelectric conversion device. In summary, the device has a lower internal resistance and higher output voltage when the concentration of KCl solution is 0.05 M, and demonstrates higher thermoelectric conversion efficiency. Moreover, improving the conductivity of the electrolyte solution without affecting the device output voltage is also a way to reduce the internal power consumption of the device. The specific power and thermoelectric conversion efficiency of the device are increased by several orders of magnitude when uniformly dispersed silver nanoparticles are added to the potassium chloride solution to enhance the conductivity of the solution. The specific power underwent an increase from 0.50 mW g⁻¹ to 42.37 mW g⁻¹, and the thermoelectric conversion efficiency also increased from 0.0022% to 0.1358%.

Nanomaterial technology is a comprehensive subject with strong intersections, and its related research content involves a wide range of modern scientific and technological fields. The science and technology in the area of nanomaterials has attracted the attention of many research groups over the past few years. By its very nature, this topic has a lot of room for research, related to very tiny objects in the nanometer range. Nanomaterials refer to the sudden changes in the properties of substances when they reach the nanometer scale, resulting in special properties. In this paper, we introduce various nanomaterials commonly used in the field of biosensing, and briefly explain the advantages and disadvantages of nanoscale biosensors. At the same time, we also explain the working principles of various types of biosensors based on nanomaterial technology, including electrochemical biosensors, optical biosensors, and piezoelectric biosensors. In addition, we also introduce the sensing targets of common biosensors, such as enzymes, DNA, microorganisms, etc. Finally, we discuss the challenges and prospects for the application of nanomaterials technology in biosensing, and analyze the current trends and future directions.

The hydrothermally synthesized rutile-TiO₂ nanorods were spin-coated with anatase-TiO₂ film and decorated with Ag nanoparticles via sputtering to construct Ag nanoparticles decorated heterophase TiO₂ composites. By extending the sputtering duration to altering the Ag content in the TiO₂ composition, we aim to investigate the correlation between the microstructures and the dual function of photoelectrochemical photocatalytic and gas-sensing performances for environmental applications. The Ag nanoparticles on the anatase/rutile-TiO₂ composites facilitate photon absorption through surface plasmon resonance. Also, Ag nanoparticles contribute the hot electron to enhance the synergy effect in the anatase-TiO₂/rutile-TiO₂ to prevent recombination of photoinduced carriers under irradiation, thereby strengthening the photocatalytic characteristics. Furthermore, the gas sensing performance is improved due to the electronic and chemical sensitization effects caused by the Ag nanoparticles on the anatase-TiO₂/rutile-TiO₂ composite. This study demonstrates that tuning Ag nanoparticle content in the anatase/rutile-TiO₂ composites is a promising material design strategy for use in highly efficient photoexcited and gas-sensing devices. The proposed Ag nanoparticles decorated polymorphic TiO₂ composite nanorods are suitable for eliminating organic pollutants in water and ethanol pollution monitoring.

In the event of a fire outbreak, it is very important to extinguish it before it becomes a blaze. Since the increase in firefighting water capacity for this purpose leads to an increase in the vehicle's load, it is necessary to reduce the weight of the tank. In this study, by changing the material from stainless steel to CFRP, the weight of the firefighting tank was reduced by 47.9% while increasing the capacity by 13.3%. The CFRP tank was manufactured by a vacuum infusion process using 12k filament carbon fiber and vinyl ester resin. After driving a firetruck equipped with a firefighting water tank for 5000 km, the dissolution test and the test to withstand the internal pressure performed on the tank corroborated that it can be equipped on firetrucks and used as a drinking water tank.

This work highlights the impact of growth temperature on the electrical and optical properties of Al-doped ZnO (AZO) films deposited by the atomic layer deposition (ALD) technique. The ALD process and super-cycle sequence have been optimized, identifying their influence on film resistivity. By using this optimum ALD procedure, the optical and electrical properties of AZO films have been widely analyzed considering the deposition temperature. Results show promising values with film resistivity in the range of 1 mΩcm and average optical absorption below 2% for 50 nm thick AZO layers. Hall effect, X-ray diffraction and ellipsometry measurements point out that these excellent values are related to their high carrier concentration and mobility, crystalline phase and optical band gap, resulting in ALD AZO films with excellent properties to be applied in photovoltaic devices as transparent conductive oxide electrode.

Silver nanoparticles, because of their large absorption surface and small size, are considered to be intelligent magnetic particles. The advancements in nanotechnology have revolutionized cancer treatment, with silver nanoparticles playing a crucial role in this field. In a recent experiment, the effects of Ag nanoparticles formulated from Origanum majorana on breast cancer cells were investigated. It was found that these nanoparticles induce apoptosis through the signal transducer and activator of transcription 3 and P53 signaling pathways. The nanoparticle characterization was conducted using FE-SEM, XRD, and UV–Vis techniques. Furthermore, the Ag nanoparticles exhibited significant antioxidant activity by preventing 50% of DPPH at 183 μg/mL. The MTT assay revealed the anti-breast carcinoma properties of silver NPs on MCF-7, T-47D, and SkBr3 cells. The outcomes demonstrated that as the nanoparticle concentration increased, the cancer cells survival percentage reduced for 3 days. The most effective anticancer effect was observed at 1000 μg/ml. MTT findings indicate that a concentration of nanoparticles at IC50 = 97, 186, and 180 μg/ml effectively targets 50% of MCF-7, T-47D, and SkBr3 breast carcinoma cells. The presence of silver NPs induces cell apoptosis, which is with the Bax markers regulation and the pro-apoptotic cleaved caspase-8 upregulation, while the anti-apoptotic Bcl-2 marker is downregulated. Besides, silver NPs inhibit the formation of colonies. Molecular pathway analysis of breast cells treated with silver NPs reveals an increase in p53 expression, while the total and phosphorylated STAT3 expression is inhibited, suggesting that p53 and STAT3 have a notable role in the remedial efficacies of silver NPs on breast carcinoma cells. Additionally, the Ag nanoparticles exhibit high sensitivity in the hydrazine electrochemical detection, a potentially carcinogenic substance, with a detection limit of 0.25 μM. The developed sensor, utilizing Ag nanoparticles, shows great promise for the environmental monitoring of hydrazine due to its excellent catalytic performance and simple preparation process. Based on clinical research, recent silver nanoparticles have emerged as a viable option for breast cancer treatment.