Traditional Metal Research Articles

Cd2+ enhancing the bromination of bisphenol A in Brassica chinensis L.: Pathways and mechanisms

Traditional heavy metal pollution, such as cadmium, impacts the transformation and risks of bisphenol pollutants (like bisphenol A, BPA), in plants, especially due to the ubiquitous presence of bromide ion. Although it has been discovered that the bromination of phenolic pollutants occurs in plants, thereby increasing the associated risks, the influence and mechanisms of bromination under complex contamination conditions involving both heavy metals and phenolic compounds remain poorly understood. This study addresses the issue by exposing Brassica chinensis L. to cadmium ion (Cd2+, 25–100 μM), with the hydroponic solution containing BPA (15 mg/L) and bromide ion (0.5 mM) in this work. It was observed that Cd2+ primarily enhanced the bromination of BPA by elevating the levels of reactive oxygen species (ROS) and the activity of peroxidase (POD) in Brassica chinensis L. The variety of bromination products within Brassica chinensis L. increased as the concentration of Cd2+ rose from 25 to 100 μM. The substitution positions of bromine were determined using Gaussian calculations and mass spectrometry analysis. The toxicity of bromination products derived from BPA was observed to increase based on Ecological Structure-Activity Relationships analysis and HepG2 cytotoxicity assays. This study provides new insights into the risks and health hazards associated with cadmium pollution, particularly its role in enhancing the bromination of bisphenol pollutants in plants.

Fe/Thiol Cooperative Hydrogen Atom Transfer Olefin Hydrogenation: Mechanistic Insights That Inform Enantioselective Catalysis.

Asymmetric hydrogenation of activated olefins using transition metal catalysis is a powerful tool for the synthesis of complex molecules, but traditional metal catalysts have difficulty with enantioselective reduction of electron-neutral, electron-rich, and minimally functionalized olefins. Hydrogenation based on radical, metal-catalyzed hydrogen atom transfer (mHAT) mechanisms offers an outstanding opportunity to overcome these difficulties, enabling the mild reduction of these challenging olefins with selectivity that is complementary to traditional hydrogenations with H2. Further, mHAT presents an opportunity for asymmetric induction through cooperative hydrogen atom transfer (cHAT) using chiral thiols. Here, we report insights from a mechanistic study of an iron-catalyzed achiral cHAT reaction and leverage these insights to deliver stereocontrol from chiral thiols. Kinetic analysis and variation of silane structure point to the transfer of hydride from silane to iron as the likely rate-limiting step. The data indicate that the selectivity-determining step is quenching of the alkyl radical by thiol, which becomes a more potent H atom donor when coordinated to iron(II). The resulting iron(III)-thiolate complex is in equilibrium with other iron species, including FeII(acac)2, which is shown to be the predominant off-cycle species. The enantiodetermining nature of the thiol trapping step enables enantioselective net hydrogenation of olefins through cHAT using a commercially available glucose-derived thiol catalyst with up to 80:20 enantiomeric ratio. To the best of our knowledge, this is the first demonstration of asymmetric hydrogenation via iron-catalyzed mHAT. These findings advance our understanding of cooperative radical catalysis and act as a proof of principle for the development of enantioselective iron-catalyzed mHAT reactions.

Strain-Modulated Flexible Bio-Organic/Graphene/PET Sensors Based on DNA-Curcumin Biopolymer.

In recent years, there has been growing interest in the development of metal-free, environmentally friendly, and cost-effective biopolymer-based piezoelectric strain sensors (bio-PSSs) for flexible applications. In this study, we have developed a bio-PSS based on pure deoxyribonucleic acid (DNA) and curcumin materials in a thin-film form and studied its strain-induced current-voltage characteristics based on piezoelectric phenomena. The bio-PSS exhibited flexibility under varying compressive and tensile loads. Notably, the sensor achieved a strain gauge factor of 407 at an applied compressive strain of -0.027%, which is 8.67 times greater than that of traditional metal strain gauges. Furthermore, the flexible bio-PSS demonstrated a rapid response under a compressive strain of -0.08%. Our findings suggest that the proposed flexible bio-PSS holds significant promise as a motion sensor, addressing the demand for environmentally safe, wearable, and flexible strain sensor applications.

Advancements in Heavy Metal Stabilization: A Comparative Study on Zinc Immobilization in Glass-Portland Cement Binders.

Recent literature has exhibited a growing interest in the utilization of ground glass powder (GP) as a supplementary cementitious material (SCM). Yet, the application of SCMs in stabilizing heavy metallic and metalloid elements remains underexplored. This research zeroes in on zinc stabilization using a binder amalgam of GP and ordinary Portland cement (OPC). This study juxtaposes the stability of zinc in a recomposed binder consisting of 30% GP and 70% OPC (denoted as 30GP-M) against a reference binder of 100% CEM I 52.5 N (labeled reference mortar, RM) across curing intervals of 1, 28, and 90 days. Remarkably, the findings indicate a heightened kinetic immobilization of Zn at 90 days in the presence of GP-surging up to 40% in contrast to RM. Advanced microstructural analyses delineate the stabilization locales for Zn, including on the periphery of hydrated C3S particles (Zn-C3S), within GP-reactive sites (Si*-O-Zn), and amid C-S-H gel structures, i.e., (C/Zn)-S-H. A matrix with 30% GP bolsters the hydration process of C3S vis-à-vis the RM matrix. Probing deeper, the microstructural characterization underscores GP's prowess in Zn immobilization, particularly at the interaction zone with the paste. In the Zn milieu, it was discerning a transmutation-some products born from the GP-Portlandite reaction morph into GP-calcium-zincate.

One-step electrodeposition synthesis of NiFePS on carbon cloth as self-supported electrodes for electrochemical overall water splitting

Electrocatalytic water splitting (EWS) for hydrogen production is considered an ideal strategy for utilizing renewable energy, reducing fossil fuel consumption, and addressing environmental pollution issues. Traditional noble metal electrocatalysts have excellent performance, but their cost is high. Developing efficient, stable, and relatively inexpensive dual functional electrocatalysts is crucial for promoting large-scale EWS hydrogen production processes. Herein, a simple one-step electrodeposition method was used to grow nickel–iron phosphorus-sulfides (NiFePS) on the surface of hydrophilic treated carbon cloth (CC). The resultant NiFePS/CC with a phosphorus to sulfur ratio of 1:4 exhibited the best electrocatalytic performance, requiring only −91 mV and 216 mV overpotentials to generate the current densities of 10 mA·cm−2 in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. When it was used as a bifunctional electrocatalyst to overall water splitting (OWS), a voltage of 1.536 V can generate a current density of 10 mA·cm−2. The excellent electrocatalytic performance can be ascribed to two factors: 1) the CC with excellent conductivity serves as a growth substrate, reducing the impedance of charge transfer from the electrode to the electrolyte and accelerating the electron transfer rate; 2) The large number of ultra-thin nanosheets formed on the surface of the catalyst increase the electrochemical specific surface area, expose more reaction sites, and thus improve the electrocatalytic reaction performance. This work provides a new approach for designing efficient non-noble metal electrocatalysts for water splitting.

Bidirectional large strain monitoring using a novel graphene film-based patch antenna sensor

This study proposes a rectangular microstrip patch antenna sensor based on a high-conductivity graphene film for bidirectional strain detection in structural health monitoring (SHM). By using a highly conductive graphene film instead of traditional metal foil to produce a patch antenna, the antenna possesses a higher flexibility and a larger sensing range. The mechanical, electromagnetic, and radiative properties were investigated. The strain sensing principle based on the resonant frequency offset of the graphene film antenna was proposed. The relationships between the resonant frequency shift and structural strain were quantitatively explored through theoretical deductions, finite element simulations, and experiments. According to the experimental results, the shift in the resonant frequency was linearly related to the lateral and longitudinal strains. The sensitivity coefficients for the lateral and longitudinal strains were 2.2037 kHz/μϵ and 3.6198 kHz/μϵ, respectively. The thermal strain can be distinguished based on the linear resonant frequency-temperature relationship. The results demonstrated the advantages and prospects of the proposed novel patch antenna for SHM.

Typical MOFs-derived nanoporous carbon: Insight into structures, properties and Pb(II) adsorption mechanism

A series of nanoporous carbon (NC) materials were synthesized by direct carbonization of traditional metal organic frameworks (MOFs) including copper-based (HKUST-1), nickel-based (Ni-MOF), zinc-based (ZIF-8), zirconium-based (UiO-66) and iron-based (Fe-BTC) for the removal of Pb(II) from simulated waste water. The physical and chemical characteristics before and after adsorption were thoroughly investigated by Fourier transforms infrared spectroscopy (FTIR), X-Ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption analyses. The adsorption kinetics and isothermal thermodynamic properties and the effects of five central different cations on the removal of Pb(II) were compared. The adsorption kinetics were well described by the quasi-second-order model and the adsorption isotherm consistent with the Langmuir equation. The adsorption process of Pb (II) is feasible, spontaneous, endothermic and reusable on the five nanoporous carbons. Among them, Fe-BTC-NC showed the best adsorption performance for Pb (II), and the maximum adsorption capacity was 479.93 mg/g. This work highlights the applications of MOFs derived nanocarbon in heavy metal contaminated water treatment and offers a facile method for the design of novel nanocarbon materials.

Analysis of the Effects of Different Orthodontic Appliances on Salivary pH Levels: An In vitro Approach.

Orthodontic appliances can influence the oral environment, including salivary pH levels, which play a crucial role in maintaining oral health. Understanding how different orthodontic appliances affect salivary pH levels can help in improving treatment outcomes and minimizing potential side effects. In this in vitro study, we evaluated the effects of various orthodontic appliances on salivary pH levels using a simulated oral environment. Four different types of orthodontic appliances were tested: traditional metal braces, ceramic braces, lingual braces, and clear aligners. Saliva samples were collected and subjected to pH measurements using a standardized method. The pH measurements were recorded at three different time intervals: immediately after appliance placement, after 24 hours, and after 48 hours. The initial pH values varied among the different orthodontic appliances: metal braces (pH 7.2), ceramic braces (pH 7.4), lingual braces (pH 7.1), and clear aligners (pH 7.5). After 24 hours, there was a decrease in pH levels for all groups: metal braces (pH 6.8), ceramic braces (pH 7.0), lingual braces (pH 6.7), and clear aligners (pH 7.2). After 48 hours, the pH levels continued to decrease: metal braces (pH 6.5), ceramic braces (pH 6.8), lingual braces (pH 6.4), and clear aligners (pH 6.9). Our findings suggest that different orthodontic appliances have varying effects on salivary pH levels. Metal braces and lingual braces tend to cause a more pronounced decrease in salivary pH compared to ceramic braces and clear aligners. Monitoring salivary pH levels during orthodontic treatment may be beneficial in identifying potential risks to oral health and implementing appropriate interventions.

Phased Array Ultrasonic Testing on Thick Glass Fiber Reinforced Thermoplastic Composite Pipe Implementing the Classical Time-Corrected Gain Method

Thermoplastic composite pipe is gaining popularity in the oil and gas and renewable energy industries as an alternative to traditional metal pipe mainly due to its capability of being spooled onto a reel and exceptional corrosion resistance properties. Despite its corrosion-proof nature, this material remains susceptible to various defects, such as delamination, fiber breakage, matrix degradation and deformation. This study employed the phased array ultrasonic testing technique with the implementation of the classical time-corrected gain method to compensate for the significant spatial signal attenuation beyond the first interface layer in the thick multi-layered thermoplastic composite pipe. Initially, the ultrasonic signals from the interface layers and back wall were detected with good signal-to-noise ratios. Subsequently, flat-bottom holes of varying depths, simulating one-sided delamination, were bored and the proposed method effectively identified ultrasonic signals from these holes, clearly distinguishing them from the background noise and interface layer signals. Finally, a defect deliberately fabricated within the composite laminate layers during the pipe manufacturing process was successfully identified. Subsequently, this fabricated defect was visualized in a three-dimensional representation using the X-ray computed tomography for a qualitative and quantitative comparison with the proposed ultrasonic method, showing a high level of agreement.

Simulation on the effect of filling porous medium on the performance of thermally conductive plastic heat sinks

High thermally conductive plastics have the characteristics of corrosion resistance, easy processing, and high thermal conductivity and can be used in corrosive environments or complex-shaped heat sinks. However, its thermal conductivity is still significantly lower than that of traditional metal heat sinks. Therefore, it is necessary to optimize the heat dissipation performance design. Based on the N–S equation and the k-ε turbulence model, the effect of porous media filled in the thermally conductive plastic heat sinks on its heat dissipation performance is studied. We compared this optimizing method with adding vortex generators in the literature. The maximum temperature of the heat sink bottom decreases by 9.3 °C. The pressure drop reduces by 55 %, and the Nusselt number increases by 9.3 %. The optimized heat sink has a hydrothermal performance factor (HTPF) 1.41. The heat dissipation performance can be similar to that of an aluminum heat sink. This study provides optimization ideas for expanding the application of thermally conductive plastics in heat sinks.

Reduced graphene oxide encapsulated octahedral NiSe2 nanocrystals with dominant {111} crystal facets for efficient hydrogen evolution reaction

Regulating the exposed crystal facets of electrocatalysts is an effective means to enhance their electrocatalytic activity. However, related studies have focused mainly on traditional noble metals or metal oxides based electrocatalysts, while the research on crystal facets dependent electrocatalytic activity of metal selenides is still very rare. Here, crystal facets effect of cubic NiSe2 in electrocatalytic HER was studied. It was shown that octahedral NiSe2 nanocrystals dominated by active {111} crystal facets exhibited significantly enhanced HER activity. Moreover, by encapsulating the octahedral NiSe2 nanocrystals into reduced graphene oxide (rGO) nanosheet networks, further improvement in their HER activity could be achieved. First principles calculations and experimental characterization indicated that {111} crystal facts of NiSe2 had abundant surface active sites and ideal catalytic reaction energy barriers. This study not only expands the research on crystal facets-dependent HER activity, but also gains a deep understanding of the electrocatalytic mechanism.

The study of the dependence of dielectric properties, electric modulus, and ac conductivity on the frequency and voltage in the Au/(CdTe:PVA)/n-Si (MPS) structures

The dielectric properties, electric modulus, loss tangent (tanδ), and ac conductivity of the fabricated Au/(CdTe:PVA)/n-Si (MPS) structures were investigated in wide-range frequency. By using the capacitance/conductance–voltage–frequency (C/G-V-f) measurements, the real/imaginary components of complex dielectric constant (εʹ, εʺ)/electrical modulus (M′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M{\\prime}$$\\end{document}, M′′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M{\\prime}{\\prime}$$\\end{document}), loss tangent (tanδ), and σac were calculated in wide-range frequency (2 kHz–0.7 MHZ) and voltage (± 2.5 V), and all results show that these parameters are a strong function of voltage and frequency. The observed decreases of εʹ and εʺ with increasing frequency were attributed to the existence of Nss, interlayer, and dipole polarizations. The value of εʹ was calculated as 128.38 (at 2 kHz and 2.5 V), which is quite higher than the maximum value of traditional SiO2. ln(σac)–ln(f) plot for 0.7 V shows three linear parts, indicating three different conduction mechanisms at low, intermediate, and high frequencies. These results show that the fabricated MPS structures can be successfully used instead of traditional metal–insulator–semiconductor as ultra-capacitors, which can use more electronic charges or energy.

A room-temperature ppb-level detection limit of NO2 sensor based on Cellulose/SnO2 heterojunction under UV illumination

In light of growing concerns over air pollution, particularly NO2 emissions from vehicular and industrial sources, there is a critical demand for advanced gas sensors. Traditional metal oxide semiconductors, while widely used, face challenges such as poor selectivity and high operating temperatures. In this work, we have achieved a high selectivity and room temperature NO2 gas sensor by composite of sponge-like porous cellulose with SnO2 nanoparticle. As a result, the gas sensor exhibits excellent performance in terms of high response (260.4 at 20 ppm), excellent selectivity and low detection limit (100 ppb) for NO2 gas, due to the unique sponge-like porous structure of cellulose with its high specific surface area facilitating the uniform distribution of SnO2 particles. This study not only highlights the superior sensing capabilities of cellulose-based sensors but also lays the foundation for further advancements in environmentally-friendly gas sensing applications.

Hydrophobic Coating on Metal Matrix Composites

Abstract: The combination of traditional aluminum metal matrix composites (MMCs) with innovative reinforcement materials offers promising avenues for enhancing material properties and expanding application domains. In this study, aluminum matrix composites reinforced with ZrB2 (zirconium diboride) particles were fabricated using a stir casting technique. The addition of ZrB2 to the aluminum matrix aimed to improve mechanical strength, wear resistance, and thermal stability. Following fabrication, the resulting composite specimens were subjected to a surface modification process involving the application of a superhydrophobic coating. The superhydrophobic coating, characterized by its extreme water repellency and self-cleaning properties, was applied to the surface of the aluminum-ZrB2 composites using a spray-coating method. The coating material consisted of a hydrophobic compound integrated with nanostructured particles, engineered to achieve a hierarchical surface morphology that mimics natural superhydrophobic surfaces. The coated specimens were evaluated for their water repellency, contact angle measurements, and durability under various environmental conditions. The results of this study demonstrated that the combination of aluminum metal matrix composites with ZrB2 reinforcement, coupled with the application of a superhydrophobic coating, yielded surfaces with exceptional water-repellent properties. The coated composites exhibited high contact angles and low water adhesion, indicative of their superhydrophobic nature. Furthermore, the durability tests revealed the robustness of the coating against mechanical abrasion and environmental exposure. Overall, the integration of aluminum-ZrB2 composites with a superhydrophobic coating holds significant promise for applications requiring water-resistant surfaces, suchas aerospace components, marine structures, and outdoor equipment. This researchcontributes to advancing the development of multifunctional materials with tailoredsurface properties, paving the way for improved performance and longevity in diverse engineering applications

Solid State and Solution Structures of Lanthanide Nitrate Complexes of Tris-(1-napthylphosphine oxide).

Coordination complexes of lanthanide metals with tris-1-naphthylphosphine oxide (Nap3PO, L) have not been previously reported in the literature. We describe here the formation of lanthanide(III) nitrate complexes Ln(NO3)3L4 (Ln = Eu to Lu) and the structures of [Ln(NO3)3L2]·2L (Ln = Eu, Dy, Ho, Er) and L. The core structure of the complexes is an eight-coordinate [Ln(NO3)3L2] with the third and fourth ligands H-bonded via their oxygen atoms to one of the naphthyl rings. The structures are compared with those of the analogous complexes of triphenylphosphine oxide and show that the Ln-O(P) bond in the Nap3PO complexes is slightly longer than expected on the basis of differences in coordination numbers. The reaction solutions, investigated by 31P and 13C NMR spectroscopy in CD3CN, show that coordination of L occurs across the lanthanide series, even though complexes can only be isolated from Eu onwards. Analysis of the 31P NMR paramagnetic shifts shows that there is a break in the solution structures with a difference between the lighter lanthanides (La-Eu) and heavier metals (Tb-Lu) which implies a minor difference in structures. The isolated complexes are very poorly soluble, but in CDCl3, NMR measurements show dissociation into [Ln(NO3)3L2] and 2L occurs.

Recent advances in polyethylene glycol as a dual‐functional agent in heterocycle synthesis: Solvent and catalyst

AbstractReactant solubility, which dictates achievable concentrations, and the stability of reaction intermediates (excited states), solvents modulate the potential energy landscape and influence reaction rates. Consequently, solvent selection is pivotal in optimizing process productivity, economic feasibility, and environmental footprint. At present, organic synthesis pivots around the idea of sustainability. In particular, PEG‐400, a popular solvent and phase transfer catalyst, is considered greener as it can be reused several times without significant loss in its catalytic activity, which checks the box regarding sustainability. This review highlights the emerging potential of Polyethylene Glycol 400 (PEG‐400) as a dual‐threat agent in sustainable organic synthesis. We explore its efficacy as a catalyst, promoting various reactions under mild conditions and often eliminating the need for traditional metal catalysts. Additionally, PEG‐400's role as a green solvent is addressed, emphasizing its biodegradability, low toxicity, and ability to facilitate reactions without hazardous Volatile Organic Compounds (VOCs). The review examines recent research on PEG‐400 mediated reactions, showcasing its effectiveness in diverse transformations, thus exploring the potential of PEG 400 as a facilitator for heterocycle synthesis in both multicomponent reactions and stepwise approaches. It identifies exciting research directions that promise to expand the boundaries of polymer‐based solvents in heterocyclic chemistry.

STUDY OF THE PERFORMANCE OF PLUNGER PUMP VALVES OPERATED IN AGGRESSIVE ENVIRONMENTS

Reciprocating plunger pumps are crucial for various industrial sectors, including chemical processing, well cementing, oil and gas production, and wastewater management. These pumps play a vital role in handling a range of fluids, making them indispensable for maintaining efficient and reliable operations in these demanding applications. These environments often involve handling aggressive fluids that can cause significant wear and corrosion to pump components, particularly the valves. Selection the right materials for valve manufacturing is essential to maintain the reliability, performance, and durability of plunger pumps operating in harsh environments. This ensures that the pumps can withstand extreme conditions while maintaining their efficiency over time. This research offers an in-depth review of the materials typically used for manufacturing plunger pump valves, with a focus on their performance in demanding environments. The research highlights the importance of material properties such as wear resistance, corrosion resistance, hardness, and mechanical strength. It evaluates various materials, including cast polyurethane, industrial ceramics such as silicon nitride and silicon carbide, and advanced coating techniques with nickel, chromium, and ceramic layers, to determine their effectiveness in harsh environments. Cast polyurethane is recognized as an optimal material due to its superior physical and mechanical properties, minimal shrinkage, and excellent chemical resistance. It excels in managing abrasive media and high-viscosity fluids, making it highly suitable for diverse industrial applications. Industrial ceramics, such as silicon nitride and silicon carbide, are distinguished by their ability to withstand high temperatures, resist corrosion, and offer low friction coefficients. Materials like silicon nitride and silicon carbide demonstrate exceptional performance in conditions where traditional metals and polymers fail. Moreover, applying advanced coatings, such as nickel-chromium-ceramic layers, to steel components significantly improves the durability and corrosion resistance of plunger rods and other critical parts. Keywords: plunger pump valves, aggressive environments, operational efficiency, material selection.

Optimal Process Parameters for FDM‐Based 3D Printing of Metal‐Polymer Mixtures with Low‐Temperature Powder Feeding

In this study, a proprietary powder‐fed 3D printer is employed to fabricate impellers from metal‐polymer mixtures via low‐temperature extrusion, simplifying the traditional complex metal molding process. By adjusting the extrusion speed and temperature, various quality impeller blanks are produced, identifying optimal printing conditions. The best results are achieved with a feed temperature of 170 °C, extrusion speed of 6 r min−1, printing platform temperature of 50 °C, and nozzle temperature of 175 °C, achieving a surface roughness of Ra = 9.973 μm. Post‐processing densification of the stainless steel wheels reach 97.23%, with a tensile strength of 255 MPa, elongation at break of 49%, and hardness of 60 HRB. These parameters meet the physical and mechanical standards required for general metal parts, demonstrating potential for precision metal processing in sectors such as aircraft engines, gas turbines, and high‐performance pumps.

Nd-, La-induced precipitate/defect in cobalt-iron magnetic alloy for strong and broadband microwave absorption

Soft magnetic microwave absorbents have merits of sufficient magnetic loss and unique magnetism-frequency response characteristics, yet are limited by the low natural resonance frequencies and simplex loss mechanism. Introducing second phase has been proven to be efficient in evoking structure, magnetism and conductivity changes, but the effects on the microwave absorption is still unbeknown. In this work, the Co0.72Fe0.28 alloy magnetic absorbents with dispersedly distributed NdCo5/LaCo5 nano precipitates were prepared. By fine-tuning the doping ratios of the rare earth (RE) of Nd/La, the coercivity and conductivity show an upward trend with enhanced magnetic and dielectric losses on 2–18 GHz. On one hand, the high magneto-crystalline anisotropic RECo5 phases uplifted the holistic resonance frequency ranges and enhanced the C/X/Ku band attenuations. On the other hand, the as-spawn vacancies, heterogeneous interfaces and dislocations boosted the conductive/polarization losses of the individual magnetic alloys. As a result, the high-frequency performance was significantly improved when ensuring the impressive low-frequency loss. A remarkable minimum reflection loss (RLmin) of −76 dB was achieved in the S band, and the effective absorption bandwidth (EAB) of 7.34 GHz was obtained at only 1.7 mm, covering most of the X/Ku bands. The performance sets it apart as the highest among the reported RE-transitional alloy absorbents so far. Overall, this work provides a feasible way and novel strategy for improving the microwave absorption properties for the traditional metal alloys and their compounds.

Atmospheric oxygen plasma-activated novel multicomponent transition metal phosphides (MnCoCu–P) for enhanced electrocatalytic water splitting to green hydrogen production: A universal catalyst across various pH electrolytes

Hydrogen (H2) is widely acknowledged as a promising, sustainable, and environmentally friendly energy carrier, offering numerous environmental benefits over conventional fossil fuels. However, the advancement of this technology is severely hindered by the scarcity of effective and robust catalysts for hydrogen evolution (HER) and oxygen evolution (OER) reactions activity. This study marks the inaugural fabrication of a hybrid tri-metallic electrocatalyst, termed MnCoCu–P, through hydrothermal synthesis. Subsequently, the catalyst undergoes atmospheric O2 plasma surface activation, aiming to amplify the efficiency of water splitting. The novel atmospheric O2 plasma-activated MnCoCu–P electrode outperforms the reported classic metal phosphides, and it outperformed the compared commercial Pt/C and RuO2 benchmark catalysts with outstanding performances of 0.488 and 1.20 V towards HER and OER at 1000 mA/cm2, respectively. Additionally, the MnCoCu–P (5 min) catalyst Faradic efficiency was calculated under alkaline conditions in 1.0 M KOH, and both the produced gas H2 and O2 match the theoretical and experimental calculated values well, indicating a high efficiency of almost 100%. In the 2-E system, MnCoCu–P (5 min)‖MnCoCu–P (5 min) demonstrated remarkable performance by attaining a current density of 1000 mA/cm2 at low total cell voltages of 1.93 V and outperforming the benchmark Pt/C‖RuO2 electrode system. On the other hand, the MnCoCu–P electrode possesses excellent activity under industrial conditions at 6.0 M @ 60 °C exhibited 1.89 V at 1000 mA/cm2 and performs well in natural water systems. Moreover, the 5 min O2 plasma-treated MnCoCu–P‖MnCoCu–P electrodes showed improved activity in all the pH solutions which makes it one of the potential candidates for commercial application in the future.