Journal of Science: Advanced Materials and Devices最新文献

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.

A novel AlGaN/GaN HEMT is proposed to improve its single event transient (SET) effect and breakdown characteristics. The device features an AlGaN back barrier layer and a buried P-GaN island in the back barrier layer (BP-HEMT). First, the P-GaN island not only modulates the electric field distribution and reduces impact ionization at both the blocking state and after ion strike but also increases the hole-electron recombination rate. Therefore, it not only effectively increases the breakdown voltage (BV), but also improves the anti-SET performance owing to decreasing the current peak after ion strike. Second, the AlGaN back barrier confines electrons in the channel, and thus, on one hand, it is beneficial to the high saturation drain current (I_d,sat) and low on-state resistance (R_on); on the other hand, it effectively prevents the electrons in the buffer layer introduced by ion strike from reaching the drain electrode both at the blocking state and after ion strike. The TCAD simulation results show that the SET peak drain current of the BP-HEMT is significantly dropped to 0.49 A/mm from 4.17 A/mm of the conventional HEMT with a linear energy transfer (LET) of 0.6 pC/μm, and the BV is significantly increased to 1318.3 V from 175.2 V, as well as the R_on decreases by 11.1%.

Energy harvesting systems, including piezoelectric (PENG), triboelectric (TENG), and pyroelectric (PYNG) nanogenerator technologies, have emerged as one of the major future energy solutions. Energy harvesting eliminates the need for conventional batteries and encourages eco-friendly alternatives. This study reports hydrothermally synthesized BaTiO₃ (BTO) particles with a tetragonal symmetry for hybrid energy harvesting. BTO particles are incorporated with PDMS at various wt% to form a flexible composite film. The 15 wt% BTO-PDMS composite/Al hybrid device (PENG-TENG) produces a peak voltage of 100 V, a current of 980 nA, and a charge of 17 nC, generating a peak power output of 33.64 μW at 100 MΩ. Furthermore, integrating this HNG (external hybridization) yielded an output of 101 V and 980 nA, demonstrating practical applicability. HNG is also employed to interact by touching various objects at different temperatures. The pyroelectric behavior of BTO allows direct thermal sensing of the object. The signals produced are processed using a convolutional neural network (CNN)-based object recognition system, which achieved a remarkable classification accuracy of 99.27% for various objects. External hybridization improves energy efficiency, representing a huge step forward in sustainable technology applications. This research paves the way for developing hybrid energy harvesters and can be employed further for extremely precise battery-free object recognition systems. This unique hybrid nanogenerator, which combines pyroelectric, piezoelectric, and triboelectric components, represents a new method of self-powered object detection. External hybridization improves energy efficiency, representing a huge step forward in sustainable technology applications.

In this study, a large size Ti-0.3Mo-0.8Ni (TA10) alloy ingot melted by electron beam cold hearth melting (EBCHM) technology was investigated. The microstructure, mechanical properties, and corrosion behavior of as-cast, hot-rolled, and annealed TA10 alloys were investigated. The results show that different states of TA10 alloys have different microstructure and properties. The microstructure of the as-cast TA10 alloy exhibits the Widmanstätten α phase, and the hot-rolled TA10 sheet shows a fibrous structure with an obvious rolling streamline. After 650 °C annealing, the intergranular β phase decreases, and most of the strip α phase changes to the equiaxed α phase. With the annealing temperature increasing to 840 °C, the microstructure gradually changed from an equiaxed structure to a duplex structure. The mechanical properties of the TA10 alloy were enhanced after hot-rolling with an increase in ultimate tensile strength from 386.5 MPa to 610 MPa. Additionally, the elongation increased from 15.6 % to 23.3 %. Upon annealing at varying temperatures, it was observed that the strength decreased, reaching to 423.5 MPa at 650 °C and 478.2 MPa at 840 °C, while the plasticity increased significantly, reaching to 26.5 % at 650 °C and 28.6 % at 840 °C. The improved strength was attributed to the better grain boundary slip of the equiaxed structure. The corrosion resistance of titanium alloys is closely connected with their microstructure. The results of the immersion corrosion test indicate that the samples in various states exhibit similar corrosion behavior. Additionally, the hot-rolled TA10 alloy shows the highest corrosion resistance, with a lower corrosion rate of 0.34459 mm/year. The as-cast TA10 alloy shows the lowest corrosion resistance, with a lower corrosion rate of 1.37559 mm/year.

Dielectric capacitors are increasingly recognized as critical components for energy storage, particularly for integrated, portable devices that demand high energy storage density and efficiency at low operating electric fields. The conventional method for increasing energy storage capacity involves polarization engineering through chemical alterations. In this study, we propose a new approach based on domain engineering by exploiting polarization vortices embedded in a paraelectric matrix. Through phase-field simulations, we demonstrate the stabilization of vortex polar structures in 0–3 PbTiO${}_3$/SrTiO${}_3$ (PTO/STO) nanocomposites. Interestingly, switching dynamics in the nanocomposites vary with changes in PTO volume fraction, resulting in paraelectric-, antiferroelectric- and ferroelectric-like polarization behaviors. The unexpected emergence of an antiferroelectric-like behavior, characterized by double hysteresis loops, is noteworthy as the component materials are not antiferroelectric. By introducing a PTO volume fraction of 0.35, an impressive discharge energy density (DED) of 2.03 J/cm${}^3$ and a high efficiency of more than 90% can be achieved in PTO/STO nanocomposites. Notably, the DED in the PTO/STO nanocomposite is 3.42 and 1.57 times higher than that of the PTO and STO component materials, respectively. The DED enhancement is attributed to the antiferroelectric–ferroelectric transition, where the high maximum polarization and eliminated remnant polarization are obtained. Additionally, the PTO/STO nanocomposite with a PTO volume fraction of 0.35 exhibits excellent thermal stability in DED over a wide temperature range of 0–300 °C. These superior properties can also be achievable in other ferroelectric/paraelectric nanocomposites. Our study offers a new avenue for enhancing energy storage capacity through the manipulation of polar topologies and polarization characteristics.

Refractory high-entropy alloys, which involve the mixing of four or more refractory metal elements in an equiatomic or near-equiatomic ratio, hold significant potential for various applications in high-temperature materials fields. This is mainly due to their stable phase structure and excellent high-temperature properties. While considerable interest has been in these alloys, most of them have been developed using melting casting technology. However, powder metallurgy has emerged as a promising alternative for further advancement in this field. It has the potential to expand the application areas and enhance the properties of these alloys. This article introduces to various techniques for fabricating pre-alloyed refractory high-entropy powders and their densification. Additionally, it reviews the methods for regulating the microstructure and properties of powder metallurgy refractory high-entropy alloys.

The current study presents a highly sensitive and selective surface-enhanced Raman scattering (SERS) based method for detecting Staphylococcus aureus (S. aureus) in food and water samples. The bioassay includes target bacteria recognition by a specific aptamer complex, fast syringe filtration and the assessment of unbound biorecognition complexes using a silver-coated porous silicon SERS platform. Notably, the developed bioassay showed high sensitivity toward S. aureus detection, achieving an impressive detection limit of 2 CFU mL⁻¹ and a broad linear response of 10¹–10⁶ CFU mL⁻¹. Furthermore, the selectivity, regeneration and overall shelf-life were thoroughly evaluated while depicting satisfactory performances. Finally, the practicality of the developed SERS bioassay was elucidated in various samples (i.e., fish, milk, groundwater and tahini) spiked with different S. aureus concentrations that revealed recovery values of 93–110%. The successful validation of actual samples' analysis emphasizes the platform's reliability, robustness and suitability for practical use, including on-site operation.

Photosynaptic transistors based on amorphous oxide semiconductors are a potential device to break von Neumann bottleneck due to their low consumption and integration of sensing, storage, and computing. Till now, there has been a lack of studies on the photosynaptic transistors based on zinc oxide (ZnO) under two dimensional optoelectronic controls. In this work, through size modulation, high-performance and back-end of line compatible 16-nm-thick ZnO thin film transistors (TFTs) by atomic layer deposition is fabricated with channel length and width of 10 and 30 μm, respectively. The device possesses outstanding electrical and photoelectric properties with a subthreshold swing of 273 mV/dec, a mobility of 28.0 cm² (V s) ¹, an on/off current ratio of 3.7 × 10⁸, high responsivity of 2.9 × 10⁵ A/W, and photo-to-dark-current ratio of 2.3 × 10¹⁰%. Moreover, three different trends of paired-pulse ratios under different V_g are exhibited with illustrations. This work demonstrates the potential of scaled down ZnO TFTs for the artificial neural networks.

Hydrotalcite-Ag nanoparticles (HT-Ag NPs) have garnered significant attention in research due to their remarkable antibacterial activity and excellent photocatalytic properties. Consequently, they have been utilized in various fields, such as pharmaceuticals, medicine, electronics, and environmental treatment. However, the synthesis of HT-Ag nanoparticles often involves the use of NaBH₄, a chemical reducing agent, to reduce Ag (I) ions and form Ag NPs on HT. Nevertheless, the residue of chemical reducing agents can lead to environmental pollution as above mentioned. The approach of utilizing plant extracts for the synthesis of Ag NPs decorated on HT has captivated many scientists due to its eco-friendly and environmentally sustainable process. Additionally, the plant extract plays a crucial role in stabilizing Ag NPs within HT-Ag structures. This paper presents a green synthesis of hydrotalcite-silver (HT-Ag) nanosheets using an AgNO₃ salt solution as a precursor and areca (Areca catechu L.) nut extract as a reducing agent. The HT nanosheets, synthesized by a co-precipitation method combined with a hydrothermal method, exhibited an ordered lamellar layer structure. The areca seed extract in 99.5 % ethanol solvent acts as a reducing agent to convert Ag(I) ions into silver nanoparticles (Ag NPs). The presence of Ag NPs on the surface of HT nanosheets was confirmed using UV–Vis spectroscopy, XRD, AAS, HR-TEM, and SEM methods. The results indicated that Ag NPs are spherical in shape and uniformly dispersed on the surface of HT. The particle size of Ag NPs ranged from 15 nm to 40 nm. The yield of the Ag NPs synthesis process on HT ranged from 60.79 % to 85.89 %, depending on the concentration of AgNO₃ salt solution. The antibacterial properties, including their effectiveness against E. coli and S. aureus, were tested using the agar well diffusion method to determine the zone of inhibition. The minimum inhibitory concentration (MIC) value of HT-Ag nanosheets has also been evaluated. Specifically, the study focused on evaluating the antibacterial activity of HT-Ag nanosheets using a marine Gram-negative bacterium, P. stutzeri B27, to explore their potential applications in materials designed for use in marine environments. Furthermore, the durability of HT-Ag nanosheets was assessed. The obtained results demonstrated that the Ag NPs decorated on HT exhibited excellent antibacterial activity against E. coli, S. aureus, and P. stutzeri B27, making them suitable for applications as antibacterial and enhancing additives for polymer systems, particularly in materials used in marine environments.

Diabetic wound healing poses a significant challenge, and there is a growing need to develop a comprehensive treatment approach in this field of research. Recently, natural lipoic acid has garnered considerable attention because it can polymerize through dynamic disulfide bonds. Here, we developed an α-lipoic acid (LA) supramolecular polymer-based hydrogel (BI-AuLA) with gold nanostars (AuNSs), in which the bovine insulin (BI) improved diabetic wound healing. The LA supramolecular polymer plays a crucial role in restoring the damaged redox microenvironment by effectively regulating the balance between reactive oxygen species and glutathione. Additionally, the photothermal properties of AuNSs enable BI-AuLA to exhibit outstanding antibacterial activity against a range of bacteria when subjected to near-infrared (NIR) irradiation. Furthermore, BI-AuLA facilitates the sustained release of BI, thereby regulating local high glucose levels in the wound. Significantly, in the diabetes mellitus skin defect model, BI-AuLA induces intensive blood vessel formation and promotes uniform collagen arrangement, thereby facilitating effective wound healing. This groundbreaking supramolecular polymer-based hydrogel represents a highly embodied and tremendously encouraging strategy for addressing the challenges posed by extensive tissue damage resulting from diabetes.