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• (MoNbTaTiZr) 1- x N x high-entropy nitride (HEN) coatings with different nitrogen contents were fabricated by magnetron sputtering. • Increasing nitrogen content caused the structural transformation in coating from pure BCC phases to nanocomposites and then to FCC polycrystalline. • (MoNbTaTiZr) 0.83 N 0.17 coating exhibited the highest hardness of 32.4 ± 2.6 GPa and H / E ratio at 0.09, together with the strongest corrosion resistance. • Densely nanocomposites with refined nanograins embedded into amorphous matrix contributed outstanding properties of (MoNbTaTiZr) 0.83 N 0.17 coating. High-entropy materials possess high hardness and strong wear resistance, yet the key bottleneck for their practical applications is the poor corrosion resistance in harsh environments. In this work, the high-entropy nitride (HEN) coatings of (MoNbTaTiZr) 1- x N x (x = 0–0.47) were fabricated using a hybrid direct current magnetron sputtering technique. The research focus was dedicated to the effect of nitrogen content on the microstructure, mechanical and electrochemical properties. The results showed that the as-deposited coatings exhibited a typical body-centered cubic (BCC) structure without nitrogen, while the amorphous matrix with face-centered cubic (FCC) nanocrystalline grain was observed at x = 0.17. Further increasing x in the range of 0.35–0.47 caused the appearance of polycrystalline FCC phase in structure. Compared with the MoNbTaTiZr metallic coating, the coating containing nitrogen favored the high hardness around 13.7–32.4 GPa, accompanied by excellent tolerance both against elastic and plastic deformation. Furthermore, such N-containing coatings yielded a low corrosion current density of about 10−8–10−7 A/cm2 and high electrochemical impedance of 106 Ω cm2 in 3.5 wt.% NaCl solution, indicating the superior corrosion resistance. The reason for the enhanced electrochemical behavior could be ascribed to the spontaneous formation of protective passive layers over the coating surface, which consisted of the dominated multi-elemental oxides in chemical stability. Particularly, noted that the (MoNbTaTiZr) 0.83 N 0.17 coating displayed the highest hardness of 32.4 ± 2.6 GPa and H/E ratio at 0.09, together with remarkable corrosion resistance, proposing the strongest capability for harsh-environmental applications required both good anti-wear and anti-corrosion performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Researchers at the University of Sao Paulo have conducted a study on the wear performance of 316L stainless steel with niobium oxide coatings in different environmental conditions, including artificial saliva. The results showed a decrease in friction coefficient, wear area, and wear rate when the coatings were applied. The study highlights the potential of these coatings for applications in the biomedical sector. For more information, readers can refer to the article "Enhancing the Wear Performance of 316L Stainless Steel with Nb [ [2] ] O [ [5] ] Coatings Deposited via DC Sputtering at Room Temperature under Varied Environmental Conditions" published in Lubricants. [Extracted from the article]

Researchers from the National Autonomous University of Mexico (UNAM) have conducted a study on pulsed direct current reactive magnetron sputtering on a silicon target. The study aimed to understand the influence of duty cycles and oxygen content on target poisoning, sputtering plasma characteristics, electric signals, and the optical and morphological properties of synthesized films. The results showed that longer duty cycles required higher oxygen levels to poison the target. The study also compared films grown via reactive pulsed DC magnetron sputtering to films grown via conventional DC magnetron sputtering. [Extracted from the article]

Researchers at Taiyuan University of Technology in Shanxi, China have conducted a study on the use of nanofilms for bone implants. They investigated the feasibility of using high-entropy alloys as coating materials for bone implants and studied the microstructure, mechanical properties, wear resistance, corrosion resistance, biocompatibility, and osteogenic activity of the nanofilms. The results showed that the refractory high-entropy alloy nanofilm exhibited superior properties, including higher hardness, better wear resistance, and excellent osteogenic activity. The researchers concluded that the high-entropy alloy nanofilm coated biomaterials could be a promising option for bone replacement. This research has been peer-reviewed. [Extracted from the article]

A new report discusses research on amino acids, specifically focusing on the detection of L-phenylalanine using a label-free Surface Enhanced Raman Spectroscopy (SERS) method. The researchers from Pondicherry University in India compared different bismuth thin films deposited by DC magnetron sputtering to select the best SERS platform. They found that the optimized bismuth thin film showed ultra-sensitive responses and enhanced sensitivity for L-phenylalanine detection. This research has potential applications in ultra-sensitive bio detections in the future. [Extracted from the article]

A recent study conducted by researchers at the University of Coimbra in Portugal explored the use of magnesium (Mg) alloys for temporary bone implants. While Mg alloys have favorable properties for biodegradability and compatibility with bone, their rapid degradation and inadequate strength limit their applicability. To address these issues, the researchers employed a surface coating technique using zirconium (Zr) to improve corrosion resistance, maintain biocompatibility, and enhance strength without compromising osseointegration. The study found that the Zr-doped coatings exhibited denser and refined structures with increasing Zr content, and demonstrated improved mechanical properties and corrosion resistance. These findings suggest the potential for using these coatings as functional biodegradable materials for temporary bone implants. [Extracted from the article]

• The structure underlying the unexpected stability of Zr-based TFMGs was tracked. • MGs with greater heterogeneity have a higher potential to form SMGs. • Slower deposition rates are required for ultrastability in more heterogeneous MGs. • The relaxation mechanism changes as the deposition rate decreases. • The geometry and distribution of loosely packed phases determines ultrastability. Ultrastable metallic glasses (SMGs) exhibit enhanced stability comparable to those of conventional glasses aged for thousands of years. The ability to understand why certain alloy compositions and processing conditions generate an SMG is an emerging challenge. Herein, amplitude-modulation dynamic atomic force microscopy was utilized for tracking the structure of Zr 50 Cu 50 , Zr 50 Cu 44.5 Al 5.5 and Zr 50 Cu 41.5 Al 5.5 Mo 3 thin film metallic glasses (TFMGs) that were produced by direct current magnetron sputtering at room temperature with the rate of deposition being the only variable. The transition in stability from bulk- to SMG-like behavior resides in the change of relaxation mechanism as the deposition rate is decreased. The formation of SMGs is directly linked with the degree of structural heterogeneity, whereby MGs with greater heterogeneity have a higher potential to form SMGs with more significant enhancement in stability. Slower deposition rates, however, are required to yield the more homogenous structure and lower energy state underlying the ultrastability. Ultrastability is closely linked with the geometric shape and distribution of loosely packed phases, whereby SMGs containing more slender loosely packed phases with a more skewed distribution achieve more significant improvements in stability. This work not only provides direct evidence of the structure of SMGs, but also opens new horizons for the design of SMGs. [Display omitted]. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amorphous WO 3-x is grown by DC sputtering, with x controlled by the oxygen pressure. • The most oxidized films show interband absorption at E g = 3.37 eV and N ∼ 1015 cm−3. • For 0 < x ≤ 0.2, W5+ states increase absorption at 1.5 eV and the electron density. • For x > 0.2, W4+ states produce absorption at 3.3 eV but no higher electron density. Tungsten oxides are interesting for a variety of applications due to their versatile optoelectronic characteristics, which can be tuned changing the composition and/or the crystalline structure. Coloration due to sub-bandgap absorption is often achieved by ion intercalation or doping in WO 3 :M films (with M = H+, Li+, Na+, etc. introducing extra electrons), but a more direct way is creating charged oxygen vacancies (V O + and/or V O 2+) in sub-stoichiometric WO 3- x forms. Here, amorphous WO 3- x thin films are obtained by reactive DC sputtering of a pure W target, on unheated glass substrates, changing the oxygen to argon pressures ratio. The control of intrinsic defects (oxygen vacancies and tungsten valence states) by the oxygen partial pressure allows tuning the morphology, sub-bandgap absorption and carrier density in these WO 3- x films, as it is proven by Raman spectroscopy, atomic force microscopy, optical spectrophotometry and Hall effect measurements. [ABSTRACT FROM AUTHOR]

SnO is an ideally suitable p-type conductive material, with large hole mobility, and has attracted great interest in connection with next-generation electronic applications. In the present work, tin oxide (SnO x) thin films were deposited on unheated soda lime glass substrates by reactive DC sputtering from a pure Sn target. The structural, optical and electrical properties of the films were analysed as a function of the oxygen partial pressure in the sputtering atmosphere and of the post-deposition annealing temperature in air. A structural analysis was carried out using Raman spectroscopy and X-ray diffraction. Optical and electrical characterizations were performed using photo-spectrometry and Hall effect measurements, respectively. The films grown at room temperature and low oxygen pressures reached high deposition rates of above 45 nm/min, showing poorly crystalline SnO and low transparency. Subsequent heating to 350 °C allowed to achieve a more crystalline tetragonal SnO with an average visible transmittance of 65%, a p-type conductivity of 0.8 S/cm, and a hole mobility of 3.5 cm2/(V s). [ABSTRACT FROM AUTHOR]

Vanadium nitride (VN) was deposited by DC-sputtering on a vertically aligned carbon nanotube (CNTs) template for the purpose of nano-structuration. This led to the fabrication of hierarchically composite electrodes consisting of porous and nanostructured VN grown on vertically aligned CNTs in a nano-tree-like configuration for micro-supercapacitor application. The electrodes show excellent performance with an areal capacitance as high as 37.5 mF cm −2 at a scan rate of 2 mV s −1 in a 0.5 M K 2 SO 4 mild electrolyte solution. Furthermore, the capacitance decay was only 15% after 20,000 consecutive cycles. Moreover, the capacitance was found to increase with VN deposit thickness. The X-ray photoelectron spectroscopy analyses of the electrodes before and after cycling suggest that the oxide layers that form at the VN surface is the responsible for the redox energy storage in this material. Such electrodes can compete with other transition metal nitride based electrodes for micro-supercapacitors. [ABSTRACT FROM AUTHOR]

However, there are no studies addressing the influence of the nitrogen/xenon gas mixture ratio in direct current magnetron sputtering on the deposition rate, physicochemical and in vitro properties of surface-modified biocompatible poly-L-lactic acid scaffolds. Keywords: Bioengineering; Biomedical Engineering; Biomedicine; Biotechnology; Electronics; Health and Medicine; Hydroxy Acids; Lactates; Lactic Acid; Magnetron; Nitrogen; Tissue Engineering; Xenon EN Bioengineering Biomedical Engineering Biomedicine Biotechnology Electronics Health and Medicine Hydroxy Acids Lactates Lactic Acid Magnetron Nitrogen Tissue Engineering Xenon 260 260 1 07/24/23 20230727 NES 230727 2023 JUL 27 (NewsRx) -- By a News Reporter-Staff News Editor at Blood Weekly -- Researchers detail new data in tissue engineering. [Extracted from the article]

In addition, the hydrogen absorption properties of Pd/ZrCo and ZrCo were tested in poisoned hydrogen mixed with 1000 ppm O [ [2] ] at 10-300 °C, where the Pd/ZrCo films maintained a better resistance to O [ [2] ] poisoning below 100 °C. Keywords: Elements; Gases; Health and Medicine; Hydrogen; Inorganic Chemicals; Poisoning EN Elements Gases Health and Medicine Hydrogen Inorganic Chemicals Poisoning 1376 1376 1 05/15/23 20230519 NES 230519 2023 MAY 19 (NewsRx) -- By a News Reporter-Staff News Editor at Health & Medicine Week -- Researchers detail new data in agriculture. [Extracted from the article]