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The structural relaxation dynamics of conventionally prepared bulk glass of N,N′-bis(3-methylphenyl)-N,N′-diphenyl-benzidine (TPD) was measured by differential scanning calorimetry. The calorimetric data were quantitatively described in terms of the Tool–Narayanaswamy–Moynihan (TNM) model. The TNM parameters were evaluated using a combination of linearization and non-linear optimization methodologies: h*/R = 109.5 kK, ln(A/s) = −321, β = 0.37, x = 0.64. In addition, the TNM phenomenology was used to describe recently reported normalized thickness data of stable and aged thin TPD films measured by ellipsometry. The structural relaxation was found to proceed at a markedly higher rate in these thin films prepared by the physical vapor deposition compared to that of conventional bulk glass. This feature appears to be associated with the significantly narrower distribution of relaxation times (β ≅ 0.8) observed for stable thin film in "as-deposited" form with uniquely dense molecular packing. Interestingly, very similar attributes of the relaxation kinetics were also found in the aged thin film with a previously erased thermal history associated with the deposition. [ABSTRACT FROM AUTHOR]

Deposition of epitaxial oxide semiconductor films using physical vapor deposition methods requires a detailed understanding of the role of energetic particles to control and optimize the film properties. In the present study, Ga 2 O 3 thin films are heteroepitaxially grown on Al 2 O 3 (0001) substrates using oxygen ion beam sputter deposition. The influence of the following relevant process parameters on the properties of the thin films is investigated: substrate temperature, oxygen background pressure, energy of primary ions, ion beam current, and sputtering geometry. The kinetic energy distributions of ions in the film-forming flux are measured using an energy-selective mass spectrometer, and the resulting films are characterized regarding crystalline structure, microstructure, surface roughness, mass density, and growth rate. The energetic impact of film-forming particles on the thin film structure is analyzed, and a noticeable decrease in crystalline quality is observed above the average energy of film-forming Ga + ions around 40 eV for the films grown at a substrate temperature of 725 ° C. [ABSTRACT FROM AUTHOR]

Photosensitization of semiconductors by excitation of chiral plasmonic metallic nanostructures has attracted much attention, not only for the analysis and detection of circularly polarized light but also for its potential applications in chiral photosynthesis. Although there have been reports on the detection of semiconductor-sensitized current in chiral nanostructures precisely fabricated by physical vapor deposition and/or lithography techniques, there have been no studies using plasmonic metal nanocolloids synthesized by chemical processes. In this study, we report the establishment of a fabrication method for large-area chiral photoelectrodes and the semiconductor photosensitization phenomenon realized using chiral plasmonic nanoparticles. Chiral plasmonic Au nanoparticles prepared by previously reported colloidal methods were immobilized onto a TiO2 thin film electrode by electrophoresis. When TiO2 electrodes loaded with chiral Au nanoparticles synthesized using L-cysteine were irradiated with circularly polarized light, left circularly polarized light irradiation at a wavelength of 500–600 nm generated a larger anodic photocurrent than right circularly polarized light irradiation at the same wavelength. This trend was reversed for TiO2 electrodes immobilized with colloidal Au nanoparticles synthesized with D-cysteine. From these results, we conclude that the efficiency of photocurrent generation by chiral plasmon excitation can be controlled by the polarization direction of the incident light. [ABSTRACT FROM AUTHOR]

Physical vapor deposition (PVD) provides a route to prepare highly stable and anisotropic organic glasses that are utilized in multi-layer structures such as organic light-emitting devices. While previous work has demonstrated that anisotropic glasses with uniaxial symmetry can be prepared by PVD, here, we prepare biaxially aligned glasses in which molecular orientation has a preferred in-plane direction. With the collective effect of the surface equilibration mechanism and template growth on an aligned substrate, macroscopic biaxial alignment is achieved in depositions as much as 180 K below the clearing point TLC−iso (and 50 K below the glass transition temperature Tg) with single-component disk-like (phenanthroperylene ester) and rod-like (itraconazole) mesogens. The preparation of biaxially aligned organic semiconductors adds a new dimension of structural control for vapor-deposited glasses and may enable polarized emission and in-plane control of charge mobility. [ABSTRACT FROM AUTHOR]

Using colloids effectively confined in two dimensions by a cell with a thickness comparable to the particle size, we investigate the nucleation and growth of crystallites induced by locally heating the solvent with a near-infrared laser beam. The particles, which are "thermophilic," move towards the laser spot solely because of thermophoresis with no convection effects, forming dense clusters whose structure is monitored using two order parameters that gauge the local density and the orientational ordering. We find that ordering takes place when the cluster reaches an average surface density that is still below the upper equilibrium limit for the fluid phase of hard disks, meaning that we do not detect any sign of a proper "two-stage" nucleation from a glass or a polymorphic crystal structure. The crystal obtained at late growth stage displays a remarkable uniformity with a negligible amount of defects, arguably because the incoming particles diffuse, bounce, and displace other particles before settling at the crystal interface. This "fluidization" of the outer crystal edge may resemble the surface enhanced mobility giving rise to ultra-stable glasses by physical vapor deposition. [ABSTRACT FROM AUTHOR]

It is always a hot and difficult problem of how to realize multi-bit data storage by preparing multi-resistance memristors by a simple process compatible with standard CMOS processes. In this work, a tristable TaO x -based memristor with tunable oxygen vacancies is fabricated by physical vapor deposition, consisting of a high-resistance state and two low-resistance states. Its set and reset voltages are low −1.1V, −2.1V, and -1V, 3.3V, respectively. The XPS characterization demonstrates the presence of three valence states within the TaO x film. It has been suggested that different barriers lead to different switching voltages during the transition of the trivalent state, resulting in the formation of stable states. Interestingly, when increasing the concentration of oxygen during preparation to decrease the concentration of oxygen vacancies in TaO x film, the volt-ampere properties of memristor change from tristable to bistable, which further proves the above point. This work provides a viable strategy for switching between bistable and tristable states in memristors prepared from transition metal oxides. [ABSTRACT FROM AUTHOR]

Supramolecular additives are an established class of nucleating agents to modify and control the solid‐state morphology of semi‐crystalline polymers, in particular isotactic polypropylene (iPP). A widely used reinforcement material for iPP is glass fibers (GFs), which significantly improve the mechanical properties. Here, these two types of materials are combined by creating defined hierarchical superstructures composed of glass microfiber nonwovens and supramolecular nanofibers based on selected 1,3,5‐benzetrisamides (BTA). The supramolecular nanofibers are prepared by physical vapor deposition (PVD), a straightforward solvent‐free process. By systematically varying PVD process parameters, it is shown that supramolecular BTA nanofibers can be reproducibly prepared on flat substrates. The morphology of the supramolecular nanofibers can be controlled by substrate temperature, evaporation time, and evaporation rate. The use of GF nonwovens enables the fabrication of hierarchical superstructures with a bottlebrush morphology comprising supramolecular nanofibers of defined length. These hierarchical superstructures are capable of nucleating iPP and thus promote transcrystallization of the iPP from the decorated GFs surface, which ultimately improves the adhesion between the GFs and the iPP. Laminating decorated GF nonwovens between two iPP films clearly increases the mechanical properties of the composites in contrast to composites without nucleating agents. [ABSTRACT FROM AUTHOR]

Vapor deposition of halide perovskites presents high potential for scalability and industrial processing of perovskite solar cells. It prevents the use of toxic solvents, allows thickness control, and yields conformal and uniform coating over large areas. However, the distinct volatility of the perovskite organic and inorganic components currently requires the use of multiple thermal sources or two‐step deposition to achieve the perovskite phase. In this work, single‐source, single‐step MA1–xFAxPbI3 thin film deposition with tunable stoichiometry by pulsed laser deposition is demostrated. By controlling the laser ablation of a solid target containing adjustable MAI:FAI:PbI2 ratios, the room temperature formation of cubic α‐phase MA1–xFAxPbI3 thin films is demonstrated. The target‐to‐film transfer of the ablated species, including the integrity of the organic molecules and the desired MA+:FA+ ratio, is confirmed by x‐ray photoelectron spectroscopy and solid‐state NMR. Photoluminescence analysis further confirms the shift of the bandgap with varying the MA+:FA+ ratio. Finally, proof‐of‐concept n‐i‐p solar cells with 14% efficiency are demonstrated with as‐deposited non‐passivated pulsed laser deposition (PLD)‐MA1–xFAxPbI3. This study opens the path for future developments in industry‐compatible vapor‐deposition methods for perovskite solar cells. [ABSTRACT FROM AUTHOR]

A study on the effect of bond coating (BC) surface modifications prior to ceramic deposition is presented. Grit blasting and polishing were used to modify the BC surface finish. Thermal barrier coating (TBC) systems were made of a commercial yttria-stabilized zirconia (YSZ) deposited by electron beam physical vapor deposition on a β-(Ni,Pt)Al-coated Ni-based single crystal superalloy. Surface roughness measurements and scanning electron microscopy observations, before and after thermal cycling at 1100 °C, were performed to investigate the influence of the initial surface treatment on the YSZ/BC interface morphology and top coat spallation resistance. Surface states enhancing TBC spallation resistance have been found. In particular, it is shown that rumpling can be avoided even in the presence of phase transformations in the BC, by grinding samples with P600 SiC paper or by applying an "heavy" grit blasting leading to a thinner BC. [ABSTRACT FROM AUTHOR]

Memristors are utilized in nonvolatile memory and artificial synaptic devices. However, the industrial application of memristors has been restricted by the occurrence of fatigue, the mechanism of which is still under debate. In this paper, we systematically investigated the mechanism of defect generation created by Joule heating in Cu-doped TiO2 memristive device. The results also demonstrated that the Joule heat for artificial synaptic emulation was less severe than that for digital data storage. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) thin films have received considerable attention due to their potential applications in various fields such as smart windows, electrochromic displays, and energy storage devices. This review highlights various methods used for the fabrication and functionalization of EC films for various applications. Various techniques for EC thin film deposition ranging from solution-processable, low-temperature approaches such as sol-gel, spin coating, dip coating, and spray pyrolysis, to advanced techniques for deposition such as physical vapor deposition, chemical vapor deposition, and sputtering are summarized in this review. In addition, various applications of EC thin films and the outcome of different deposition approaches on the opto-electrochromic properties of EC thin films have been discussed elaborately. This review has the potential to spark the interest of researchers from a broad range of disciplines, including photocatalysis, electrocatalysis, nanotechnology and materials science. [ABSTRACT FROM AUTHOR]

We present a comparative molecular dynamics simulation study of copper film growth between various physical vapor deposition (PVD) techniques: a constant energy neutral beam, thermal evaporation, dc magnetron sputtering, high-power impulse magnetron sputtering (HiPIMS), and bipolar HiPIMS. Experimentally determined energy distribution functions were utilized to model the deposition processes. Our results indicate significant differences in the film quality, growth rate, and substrate erosion. Bipolar HiPIMS shows the potential for an improved film structure under certain conditions, albeit with increased substrate erosion. Bipolar HiPIMS (+180 V and 10% Cu+ ions) exhibited the best film properties in terms of crystallinity and atomic stress among the PVD processes investigated. [ABSTRACT FROM AUTHOR]

Wireless local area network (WLAN) has gained widespread application as a convenient network access method, demanding higher network efficiency, stability, and responsiveness. High-performance filters are crucial components to meet these needs. Film bulk acoustic resonators (FBARs) are ideal for constructing these filters due to their high-quality factor (Q) and low loss. In conventional air-gap type FBAR, aluminum nitride (AlN) is deposited on the sacrificial layer with poor crystallinity. Additionally, FBARs with single-crystal AlN have high internal stress and complicated fabrication process. These limit the development of FBARs to higher frequencies above 5 GHz. This paper presents the design and fabrication of FBARs and filters for WLAN applications, combining the high electromechanical coupling coefficient ( K t 2 ) of Al0.8Sc0.2N film with the advantages of the thin film transfer process. An AlN seed layer and 280 nm-thick Al0.8Sc0.2N are deposited on a Si substrate via physical vapor deposition (PVD), achieving a full width at half maximum (FWHM) of 2.1°. The ultra-thin film is then transferred to another Si substrate by wafer bonding, flipping, and Si removal. Integrating conventional manufacturing processes, an FBAR with a resonant frequency reaching 5.5 GHz is fabricated, demonstrating a large effective electromechanical coupling coefficient ( k eff 2 ) of 13.8% and an excellent figure of merit (FOM) of 85. A lattice-type filter based on these FBARs is then developed for the Wi-Fi UNII-2 band, featuring a center frequency of 5.5 GHz and a −3 dB bandwidth of 306 MHz, supporting high data rates and large throughputs in WLAN applications. [ABSTRACT FROM AUTHOR]

Thin‐film rechargeable batteries have a wide range of applications due to their unique properties such as small size, thinness, and the ability to power smart devices, including portable electronic devices, medical devices, smart cards, RFID tags, and Internet of Things (IoT) devices. Processing thin‐film electrodes for these batteries generally relies on standard physical vapor deposition technologies. However, producing porous thin‐films using these techniques presents significant challenges. Here, a rapid and cost‐effective chemical route for processing porous vanadium oxide (V2O5) thin‐film cathodes for application in Zinc‐ion‐based thin‐film batteries (Zn‐TFBs) is explored. The V2O5 precursor process uses an industrially viable spraying technique, which not only offers impressive charge storage performance of an areal capacity of 47.34 µAh cm−2, areal energy of 50.18 µWh cm−2, and areal power of 53 µW cm−2 at 50 µA cm−2 in the optimized gel‐electrolyte composition. This study introduces a cost‐effective and industrially viable method for processing highly porous thin‐film cathodes, enabling the production of high‐performance, affordable, and safer thin‐film batteries. [ABSTRACT FROM AUTHOR]

The effect of the spatial arrangement in the physical vapor deposition (PVD) chamber on the composition and properties of coatings is considered using the example of the deposition of the (Ti,Al)N coating. The proposed method is one of the ways (along with varying the arc current of the cathodes and the bias voltage, as well as using alloy cathodes) to change the ratio of elements in the coating, and achieves this across a wide range of values. The three samples were located, respectively, opposite the evaporator with a titanium cathode, opposite the evaporator with an aluminum cathode and in an intermediate position between the two evaporators. The coating was deposited without rotating the turntable. The aluminum content in the coatings decreases from 94.2 at.% for the sample located directly opposite the evaporator with an Al cathode to 10.3 at.% for the sample located opposite the evaporator with a Ti cathode. In the coating deposited on the sample located opposite the aluminum cathode, the formation of a nitrided layer with a thickness of about 250 nm was observed in the substrate. The maximum hardness (32.3 ± 1.7 GPa) belongs to a coating on the sample occupying an intermediate position. The coating on the sample located opposite the aluminum cathode has a hardness of 16.7 ± 0.8 GPa. The coating hardness on the sample located opposite the titanium cathode is 28.5 ± 1.1 GPa. The best fracture strength in the scratch test was observed for the coating on the sample occupying an intermediate position. The nature of the coating fracture in the scratch test was studied. A sufficiently high-quality coating can be obtained without rotating the turntable, and the coating composition can be controlled by changing the position of the sample relative to the evaporators. [ABSTRACT FROM AUTHOR]

Rechargeable lithium batteries (LBs) are considered the most promising electrochemical energy storage systems for utilizing renewable energies like solar and wind, ushering society into an electric era. However, the development of LBs faces challenges due to interfacial issues caused by side reactions between existing electrode and electrolyte materials. Magnetron sputtering (MS), a type of physical vapor deposition technology, offers solutions with its wide material selection, gentle deposition process, high uniformity of nano/micro‐scale thin films, and strong thin‐film adhesion. This review outlines the main operating principles of MS technology and explores its advanced applications in interfacial modification of various cathodes, anodes, separators, solid‐state electrolytes, and thin‐film LBs integrated with other microelectronic devices. Furthermore, the review discusses the potential of MS technology to accelerate scientific research and industrial progress toward higher‐performance LBs, advancing human society. [ABSTRACT FROM AUTHOR]

Interface engineering is a promising strategy for controlling the Curie temperature (Tc) and perpendicular magnetic anisotropy (PMA) in magnetic 2D van der Waals (2D vdWs)‐based heterostructures. However, establishing high‐quality interface structures in magnetic 2D vdWs/metal stacks, crucial for maximizing interface effects, remains a significant challenge. Here, a Fe5‐xGeTe2/Pt (F5GT/Pt) prototype with a superior interface quality is achieved using a low‐power physical vapor deposition technique. The magnetic properties of the F5GT/Pt heterostructures are strongly influenced by employing the specific physical deposition method. Stable ferromagnetism at 400 K is observed when depositing Pt atoms with relatively high energy, despite the Tc of pristine F5GT being below 300 K. This unexpected high‐temperature ferromagnetism is attributed to the formation of a ferromagnetic alloy at the interface, commonly present in vdWs‐based stacks fabricated through physical deposition but often overlooked. The deposit of Pt atoms with ultralow energy leads to the formation of a unique Fe5‐xGeTe2/Fe3‐xGeTe2 heterojunction at the interface, significantly enhancing the PMA. This work emphasizes the importance of interface structures in vdWs‐based devices, suggesting that controlling the growth process offers an effective approach to construct and engineer vdWs heterostructures, thus improving the performance and introducing new functionalities to spintronic devices. [ABSTRACT FROM AUTHOR]

Molybdenum Trioxide (MoO3) is a promising candidate as an anode material for lithium‐ion batteries (LIB), with a theoretical capacity of 1 117 mAhg−1. Nevertheless, MoO3 has inherent lower electronic conductivity and suffers from significant volume expansion during the charge–discharge cycle, which hinders its ability to attain a substantial capacity and cyclability for practical applications. In this study, a novel material design strategy is reported for LIB anodes containing MoO3 and hard carbon (HC) architecture fabricated using a Physical Vapor Deposition (PVD) technique. MoO3/HC as anode materials are evaluated for LIBs, which demonstrate an exceptional performance with a capacity of 953 mAhg−1 at a discharging rate of 0.2 C. Additionally, MoO3/HC anode demonstrated exceptional rate capability during fast charging at 5 C and achieved a capacity of 342 mAhg−1. The MoO3/HC anode demonstrates remarkable cycle life, retaining over > 99% Coulombic efficiency after 3 000 cycles at a rate of 0.2 C. The exceptional performance of MoO3/HC anode can be attributed to the novel material design strategy based on a multi‐layered structure where HC provides a barrier against the possible volumetric expansion of LIB anode. [ABSTRACT FROM AUTHOR]

Bis(8‐hydroxyquinolates) Zinc (Znq2) can be used as a light‐emitting layer material in OLED devices to achieve its efficient electroluminescence effect. In this paper, Znq2 powder has been successfully synthesized and modified by the physical vapor deposition (PVD) method. Precursors and nano‐materials are characterized by XRD, SEM, PL, and so on. The performance of the modified material has been significantly improved. The emission intensity and absorption intensity in the deposited products increased with the increase in PVD temperature. At 453 K, luminous properties such as luminous intensity reach the optimal value including its fluorescence lifetime. Fluorescence lifetime values vary from 13 to 17 ns with the increase in temperature. The luminescence mechanism is also discussed. The energy gap and absorption spectrum of HOM‐LUMO are calculated by the DFT/UB3LYP method. The experimental values agree well with the theoretical values. The nanomaterial crystals modified by PVD technology are more orderly, impurities are reduced, and the luminous stability of the material is improved, which may be one of the reasons for the relatively slow decline in product life. The research combined with theoretical simulation is expected to be helpful to the research and promotion of such materials. [ABSTRACT FROM AUTHOR]

The corrosion behavior of the TiN monolayer and CrN/TiN multilayer coatings deposited via cathodic arc evaporation physical vapor deposition (CAE‐PVD) on the Ti–6Al–4V substrates were evaluated in Ringer's and Hank's physiological saline electrolytes. XRD (x‐ray diffractometry) and scanning electron microscopy (SEM) analysis were used to characterize the coatings. The corrosion behavior of coatings was assessed by impedance spectroscopy and potentiodynamic polarization techniques. The results showed that the corrosion resistance of coatings was increased in the order of TiN‐Ringer's < TiN‐Hank's < CrN/TiN‐Ringer's < CrN/TiN‐Hank's. Therefore, it can be concluded that the CrN/TiN coating, due to having a large number of interfaces and a smoother surface with fewer macroparticles and pinholes, is more efficient in raising the corrosion resistance properties of titanium than TiN monolayer coating. Moreover, it was observed that Ringer's solution is a more severe environment than Hank's solution. Both coatings, because of the precipitation of a protective corrosion products layer on their surface, showed an enhancement in corrosion resistance with increasing the immersion time from 1 to 14 days in Hank's. The results suggest TiN monolayer and CrN/TiN multilayer coatings as promising candidates for biomedical applications. [ABSTRACT FROM AUTHOR]

We report on the molecular beam epitaxial growth and characterization of polarity-controlled single and multi-layer Scandium Aluminum Nitride (ScAlN) transduction structures grown directly on ScAlN templates deposited by physical vapor deposition (PVD) on Si(001) substrates. It is observed that direct epitaxial growth on PVD N-polar ScAlN leads to the flipping of polarity, resulting in metal (M)-polar ScAlN. By effectively removing the surface impurities, e.g., oxides, utilizing an in situ gallium (Ga)-assisted flushing technique, we show that high quality N-polar ScAlN epilayers can be achieved on PVD N-polar ScAlN templates. The polarity of ScAlN is confirmed by utilizing polarity-sensitive wet chemical etching and atomic-resolution scanning transmission electron microscopy. Through interface engineering, i.e., the controlled formation or removal of surface oxides, we have further demonstrated the ability to epitaxially grow an alternating tri-layer piezoelectric structure, consisting of N-polar, M-polar, and N-polar ScAlN layers. Such multi-layer, polarity-controlled ScAlN structures promise a manufacturable platform for the design and development of a broad range of acoustic and photonic devices. [ABSTRACT FROM AUTHOR]

This study investigates the impact of multi-step austenitization heat treatment on the in-service life of modified AISI A8 cold work tool steel knives used in wood cutting. The knives were subjected to two treatment methods: single quenching and double tempering (SQDT) and double quenching and double tempering (DQDT). Both treatments were followed by physical vapor deposition (PVD) coating to enhance surface properties. The DQDT treatment resulted in a finer microstructure and more uniform carbide distribution. Field tests on 24 knives over 124 h demonstrated up to 130% improvement in wear resistance for DQDT knives, along with superior edge stability and better PVD coating preservation. DQDT knives exhibited ductile fractures characterized by dimples, contrasting with the brittle fracture and cleavage facets in SQDT knives. Residual stress measurements showed higher compressive stresses in DQDT knives (−280 MPa) compared to SQDT knives (−30 MPa), which increased further after field testing. The enhanced performance of DQDT knives is attributed to their refined microstructure, improved carbide distribution, and higher compressive residual stresses, offering significant potential for improving wood cutting tool efficiency and durability. [ABSTRACT FROM AUTHOR]

Vertically aligned carbon nanotubes (VACNTs) exhibit outstanding mechanical strength, chemical stability, and electrical characteristics; however, their constrained mechanical elasticity and chemical responsiveness spurred research on atomic decoration techniques for enhancing their mechanochemical attributes. Nevertheless, achieving uniform atomic decoration on the VACNT surface is difficult because of the high density and large aspect ratio of VACNT. Herein, a strategy to design and apply nanopatterned VACNTs (nVACNTs) based on a nanotransfer printing process is proposed to improve atomic penetrability. Nanopatterns inherent to nVACNTs facilitate atomic penetration, allowing for the more consistent and higher quality deposition of functional materials such as zinc oxide and alumina by atomic layer deposition. Furthermore, physical vapor deposition provides an improved coating of metal catalysts such as gold. The uniform deposition of ceramic layers on the entire surface of nVACNTs strengthens its mechanical resilience, owing to the diminished van der Waals forces of CNTs. Surface‐decorated nVACNTs display an increased sensitivity to NO2 gas, which is attributed to the enhanced quality of the reactive catalyst deposition and augmented permeability. This strategy achieves a larger decorated area while increasing a catalytically active reaction area. The obtained results promise that the enhanced nVACNTs will expand the industrial applications of carbon nanotubes. [ABSTRACT FROM AUTHOR]

The durability of thermal barrier coatings (TBCs) is significantly influenced both by the ceramic top coat and the bond coat. In this study, novel YbGdZrO ceramic coats were deposited on the surfaces of three types of Cr-modified (Ni, Pt)Al bond coats via electron beam physical vapor deposition (EB-PVD) technique. These Cr-modified (Ni, Pt)Al bond coats were fabricated by magnetic sputtering Cr onto the (Ni, Pt)Al bond coats with varying sputtering times of 30, 60, and 90 min. The results indicates that the thickness of the Cr-modified layer increases with the extension of sputtering time. A short deposition time of 30 min is adequate for achieving an appropriate Cr content in the (Ni, Pt)Al bond coats, which ensures selective oxidation of Al element within the bond coat and further enhances the metallurgical interfacial bonding strength with the ceramic coat by adapting to the concentration gradient diffusion. However, as the sputtering time is extended to 60 and 90 min, α-Cr begins to form in the Cr-modified (Ni, Pt)Al bond coats, which negatively affects the oxidation resistance of the bond coat. Consequently, the thermal shock life of the TBCs samples is significantly reduced with increasing sputtering time. The longest thermal shock lifetime is obtained on the bond coat with Cr plating time of 30 min owing to a differing thermally grown oxide formation and failure mechanism. [ABSTRACT FROM AUTHOR]

One of the physical methods for obtaining magnetite nanoparticles (NPs) is electron beam physical vapor deposition (EB PVD), which requires complex equipment, but allows obtaining a significant amount of pure (ligand-free) NPs. The biomedical application of such NPs is less studied than materials from other synthesis methods. The objective is to study the effect of pure magnetite NPs in the NaCl matrix obtained by EB PVD on hematological indicators, gases, electrolytes and parameters of iron metabolism in the blood of intact animals. The physical characteristics of NPs were studied using high-resolution transmission electron microscopy, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping, electron energy-loss spectroscopy, selected area electron diffraction and fast Fourier transform. In vivo experiments were conducted on albino male rats, which were injected with solution of magnetite-sodium chloride NPs (1.35 mg Fe/kg). After 3 and 72 h, hematological parameters, blood gases, electrolytes, and serum iron were determined. The synthesized NPs had an average size of 11 nm. They were identified as magnetite, where polycrystals and single crystals were present. The absence of contamination in crystal boundaries, clear orientation and orderliness of atoms in crystals were established. The administration of NPs in the sodium chloride matrix to animals was characterized by a transient increase in the main indicators of red blood accompanied by an increase in the saturation of erythrocytes with hemoglobin and their mean volume after 3 h. It did not worsen blood gases and pH, but decreased blood Na+ content after 72 h. The investigated NPs caused changes in the parameters of serum iron characteristic to iron preparations, which after 3 h were smaller compared to the reference iron drug, and after 72 h—similar to it. More intense rapid effects on hematological parameters at lower serum iron indicate greater activity of the studied pure magnetite NPs obtained by EB PVD syntesis compared to the reference iron preparation. Highlights: Pure magnetite nanoparticles in the NaCl matrix were obtained by EB PVD. They were studied using high-resolution transmission electron microscopy. These nanoparticles had a size of 11 nm, clear orientation and orderliness of atoms in crystals. In healthy animals, they caused a transient increase in red blood indicators. They did not worsen blood gases and pH, but decreased Na+ content in the blood. The nanoparticles caused changes in the serum iron typical to iron preparations. These changes were not toxic and lasting due to compensatory reactions. [ABSTRACT FROM AUTHOR]

Bioresorbable magnesium-metal vascular stents are gaining popularity due to their biodegradable nature and good biological and mechanical properties. They are also suitable candidate materials for biodegradable stents. Due to the rapid degradation rate of Mg metal vascular scaffolds, a Mg/Zn bilayer composite was formed by a number of means, such as magnetron sputtering and physical vapor deposition, thus delaying the degradation time of the Mg metal vascular scaffolds while providing good radial support for the stenotic vessels. However, the interlaminar compounds at the metal interface have an essential impact on the mechanical properties of the bi-material interface, especially the cracking and delamination of the Mg matrix Zn coating vascular stent in the radially expanded process layer. Intermetallic compounds (IMCs) are commonly found in dual-layer composites, such as Mg/Zn composites and multi-layer structures. They are frequently overlooked in simulations aiming to predict mechanical properties. This paper analyses the interfacial failure processes and evolutionary mechanisms of interfacial fracture mechanics of a Mg/Zn interface with an intermetallic compound layer between coated Zn and Mg matrix metallic vascular stents. The simulation results show that the fracture mode in the Mg/Zn interface with an intermetallic compound involves typical ductile fracture under static tensile conditions. The dislocation line defects mainly occur on the side of the Mg, which induces the Mg/Zn interfacial crack to expand along the interface into the pure Mg. The stress intensity factor and the critical strain energy release rate decrease as the intermetallic compound layer's thickness gradually increases, indicating that the intensity of stress and the force of the crack extending and expanding along the crack tip are weakened. The presence of intermetallic compounds at the interface can significantly strengthen the mechanical properties of the material interface and alleviate the crack propagation between the interfaces. [ABSTRACT FROM AUTHOR]

• The Mg@Ni foam material is proposed and prepared for the first time. • This material can deliver 1018 ml g−1 H 2 in 10 min in 5 wt.%NaCl solution at 25 °C. • This material has a high antioxidant capacity and its hydrogen generation is controllable. • The advances come from the unique Mg-Ni foam composite structure. As a promising in-situ hydrogen generation material, magnesium (Mg) has been seeking a promotion in its hydrogen generation property. Increasing the specific surface area, for example, replacing the Mg bulk using Mg powder, can greatly increase the hydrogen generation property, but it brings a high explosion risk, a difficulty in controlling the hydrogen generation, and an oxidation problem. In this work, we prepare a novel Mg@Ni foam material with Mg deposits on Ni foam by a physical vapor deposition method. The Ni foam not only increases the hydrolysis reaction areas of Mg by improving its specific surface area, but also kinetically accelerates the hydrolysis reaction rate of Mg by forming a uniform Mg-Ni galvanic cell. As a result, the Mg@Ni foam material realizes a near-theoretical hydrogen generation amount of Mg and a hydrogen generation rate significantly higher than those realized by the bulk Mg-based materials. The Mg@Ni foam material with the excellent hydrogen generation property is also free from explosion risk, easy to be controlled, and resistible to oxidation. A hydrogen fuel cell powered by the hydrogen generated by the Mg@Ni foam material can yield a steady voltage and run a small car for a long distance. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted widespread attention due to their low cost and high efficiency. So far, a variety of single‐junction PSCs have been successfully developed and considered for commercialization, including normal PSCs (N‐PSCs), inverted PSCs (I‐PSCs), and carbon‐based PSCs (C‐PSCs) without hole transporter. Herein, the material cost, equipment depreciation cost, and energy consumption of these three types of PSCs (1 m2) in detail are analyzed. As indicated, the total fabrication cost of the N‐PSCs ($86.49) and I‐PSCs ($81.31) is very close, but is significantly reduced to $41.16 for the C‐PSCs (49%–52% reduction) because carbon electrode is much cheaper than noble metal electrode and organic hole transporter. Besides, only a low‐cost slot‐die coating process with low energy consumption is needed for the deposition of carbon electrode, while the expensive physical vapor deposition and reactive plasma deposition processes with high energy consumption are needed for the deposition of the noble metal electrode and organic hole transporter. [ABSTRACT FROM AUTHOR]

Face‐centered cubic (fcc) metals deposited onto crystalline substrates grow heteroepitaxially with specific orientation relationships (ORs). The ORs depend on a number of factors including lattice mismatch, bonding and the relative symmetry between the surface and the film. Less explored factors include defects like growth and annealing twins. In this study, a high density of nanotwins in as‐deposited films delay grain growth of OR1 ({111}fcc∥(0001)Al2O3$\left(\left{\right. 111 \left.\right}\right)_{f c c} \parallel \left(\left(\right. 0001 \left.\right)\right)_{A l_{2} O_{3}}$, ⟨110⟩fcc∥⟨101¯0⟩Al2O3$\left(\langle 110 \rangle\right)_{f c c} \parallel \left(\langle 10 \bar{1} 0 \rangle\right)_{A l_{2} O_{3}}$) grains up to 0.56 Tm. A new OR with respect to the c‐sapphire substrate is found, compared to the well‐known OR1 and OR2 which grow with the {111}fcc$\left(\left{\right. 111 \left.\right}\right)_{f c c}$∥(0001)Al2O3$$ \parallel {(0001)}_{A{l}_{2}{O}_{3}}$$. This is named OR3, grows above 0.56 Tm with {001}fcc∥(0001)Al2O3,⟨100⟩fcc∥⟨101¯0⟩Al2O3$\left(\left{\right. 001 \left.\right}\right)_{f c c} \parallel \left(\left(\right. 0001 \left.\right)\right)_{A l_{2} O_{3}} , \left(\langle 100 \rangle\right)_{f c c} \parallel \left(\langle 10 \bar{1} 0 \rangle\right)_{A l_{2} O_{3}}$. The OR3 growth is related to strain and defect energy advantage. An unusual OR {345}fcc∥(0001)Al2O3$\left(\left{\right. 345 \left.\right}\right)_{f c c} \parallel \left(\left(\right. 0001 \left.\right)\right)_{A l_{2} O_{3}}$accompanies OR3 in most films, occupying an area fraction of >0.3. A minute (<0.05) but consistent fractions of {447}fcc$$ \{447{\}}_{fcc},$$, {115}fcc$$ \{115{\}}_{fcc}$$, {221}fcc$$ \{221{\}}_{fcc}$$, {236}fcc$$ \{236{\}}_{fcc}$$ and 146fcc$$ {\left\{146\right\}}_{fcc} $$ all parallel to 0001Al2O3$$ {\left(0001\right)}_{A{l}_{2}{O}_{3}}$$ and related to annealing twins in exact and near {001}fcc$\left(\left{\right. 001 \left.\right}\right)_{f c c}$ and {111}fcc$\left(\left{\right. 111 \left.\right}\right)_{f c c}$ grains are observed. The study opens new directions in the crystallography of ORs, considering the role of twins in addition to the surface and strain energies. [ABSTRACT FROM AUTHOR]

We present a systematic growth study of epitaxial RuO2(110) and IrO2(110) on TiO2(110) substrates by pulsed laser deposition. We describe the main challenges encountered in the growth process, such as a deteriorating material flux due to laser-induced target metallization or the delicate balance of under- vs over-oxidation of the "stubborn" Ru and Ir metals. We identify growth temperatures and oxygen partial pressures of 700 K, 1 × 10−3 mbar for RuO2 and 770 K, 5 × 10−4 mbar for IrO2 to optimally balance between metal oxidation and particle mobility during nucleation. In contrast to IrO2, RuO2 exhibits layer-by-layer growth up to 5 unit cells if grown at high deposition rates. At low deposition rates, the large lattice mismatch between film and substrate fosters initial 3D island growth and cluster formation. In analogy to reports for RuO2 based on physical vapor deposition [He et al., J. Phys. Chem. C 119, 2692 (2015)], we find these islands to eventually merge and grow to continue in a step flow mode, resulting in highly crystalline, flat, stoichiometric films of RuO2(110) (up to 30 nm thickness) and IrO2(110) (up to 13 nm thickness) with well-defined line defects. [ABSTRACT FROM AUTHOR]

The most important cutting materials for machining are carbides. Their production requires both tungsten and cobalt; however, these materials are becoming increasingly difficult to obtain and are sometimes mined under ethically questionable conditions. As a result, increasing efforts are being made to expand the range of cutting materials. The basic suitability of natural rocks for cutting tools in less demanding processes has already been demonstrated. PVD coating of the natural rocks could improve their performance. The adhesion mechanisms in TiN-coated natural rock samples are discussed below. The TiN thin film is characterized in depth. [ABSTRACT FROM AUTHOR]

Plasmonic structural color originates from the scattering and absorption of visible light by metallic nanostructures. Stacks consisting of thin, disordered semicontinuous metal films are attractive plasmonic color media, as they can be mass-produced using industry-proven physical vapor deposition techniques. These films are comprised of random nano-island structures of various sizes and shapes resonating at different wavelengths. When irradiated with short-pulse lasers, the nanostructures are locally restructured, and their optical response is altered in a spectrally selective manner. Therefore, various colors are obtained. We demonstrate the generation of structural plasmonic colors through femtosecond laser modification of a thin aluminum film–isolator–metal mirror (TAFIM) structure. Laser-induced structuring of TAFIM's top aluminum film significantly alters the sample's specular and diffuse reflectance depending on the fluence value and the number of times a region is scanned. A "negative image" effect is possible, where a dark field observation mode image is a negative of a bright field mode image. This effect is visible using an optical microscope, the naked eye, and a digital camera. The use of self-passivating aluminum results in a long-lasting, non-fading coloration effect. The reported technique could be used in anti-counterfeiting and security applications, as well as in plasmonic color printing and macroscopic and microscopic marking for personalized fine arts and aesthetic products such as jewelry. [ABSTRACT FROM AUTHOR]

In this work, a comparative study of the tribological performance of two hard coatings, CrN/TiBN, was conducted for research purposes and industrial applications in food products, particularly for food packaging into cans using the double hermetic sealing process. CrN and TiBN coatings were successfully deposited on a base-cobalt metal substrate of a CoCrW commercial alloy using physical vapor deposition by arc evaporation (AEPVD) technology to improve the tribological properties of the commercial alloy, including wear and corrosion resistance, lower coefficient of friction, and overall durability. This research focuses on conducting scratch and abrasion wear resistance tests in dry conditions; specifically, it pursues to evaluate the wear corrosion properties, known as tribocorrosion performance, on CrN/TiBN hard coatings. The experimental results show that the CrN coating (2.9 μm) is slightly thicker than the TiBN coating (2.7 μm), with a 47 N critical load. It also shows a lower coefficient of friction (CoF) in a dry environment, while the TiBN coating showed total detachment and a high coefficient of friction in a dry environment condition. Tribocorrosion testing in brine aqueous solution indicated that CrN coating shows a high friction coefficient with a higher open circuit potential value (Ecorr), and TiBN shows the lowest corrosion potential (Ecorr) and the lowest friction coefficient. This suggests that CrN could provide better corrosion protection for commercial cobalt alloys and improve tool performance during the food canning process in brine environments. [ABSTRACT FROM AUTHOR]

Photocatalytic coatings have the potential to contribute to the purification of water via an advanced oxidation process (AOP). A commonly used method for analyzing the mechanism of the photocatalytic performance of a given reactor type is to document the degradation behavior in a solution containing methylene blue. However, since methylene blue is rather unstable, the degradation results should be viewed critically. In this work, the degradation behavior of a test solution with methylene blue on quartz glass surfaces coated with photocatalytic titanium dioxide (TiO2) of the anatase modification was investigated through a variety of different light sources. The coating was deposited by physical vapor deposition (PVD) with the reactive pulsed DC magnetron sputtering ion plating (MSIP) method described in the study by Desch and Lake, while the quartz glasses were coated with a 100 nm thick TiO2 coating on the outside. The same glasses were used for all experiments with TiO2. In the determination of the degradation rate, additional experiments were performed using pure quartz glass without any coating, which made it possible to examine the influence of different light sources on the degradation rate of methylene blue in general. Three different light sources, namely UV‐A, UV‐C, and simple fluorescent lamps were used in this study. The concentration of methylene blue was recorded by photo spectrometer in 10‐min increments throughout the experiment and the experiments were performed for 24 h in all cases. Our data indicates that the methylene blue test is a poor method because the degradation rate is not clearly differentiable due to the low stability of the test substance. Without including reference testing in the absence of a catalyst, data may be subject to misinterpretation. [ABSTRACT FROM AUTHOR]

Titanium carbo-nitride (TiCN) comes under the metal nitride group which can provide a combined property of titanium carbide (TiC) and titanium nitride (TiN) coating. TiCN Coating possess an excellent mechanical and tribological, properties which leads its application in many industries particularly in the Automotive and aerospace industries. TiCN films can be very hard and strong based on the composition and synthesis process. Physical Vapor Deposition (PVD) technique is widely used for the preparation of thin film coating because of its ability to precisely control the composition and thickness of the coatings. The properties of the developed coating significantly affect by the PVD process parameters and their levels. Multi-Criteria Decision Making (MCDM) methods are widely used in many sectors for the selection of process parameters based upon some specific criteria. In the present work TiCN coatings were synthesized by using one of the most widely used PVD method called magnetron sputtering. L16 orthogonal array was used as a design of experiment for the experimental work by varying the sputtering process parameters like bias voltage, N2 flow rate and substrate to target distance. After the synthesis, the developed films were tested using atomic force microscopy (AFM), Scanning electron microscopy (SEM), and Nanoindentation. From the characterization three response parameters such as hardness (H), Modulus of elasticity (E) and surface roughness (Ra) of the coating has been considered. A hybrid method based on improved removal effects of criteria- technique for order performance by similarity to ideal solution (MEREC-TOPSIS) approach has been considered for the for the process parameters selection. The results have also been compared with other weight calculation techniques. In all the cases it is observed that experiment no 16 and 15 have got the 1st and second rank respectively. However, experiment no 1 is the last rank in all the cases. From the correlation analysis it is found a strong positive correlation between MEREC-TOPSIS and other methods. The method provides a significant advancement in the selection of optimal parameters, ensuring enhanced coating properties crucial for industrial applications [ABSTRACT FROM AUTHOR]

As a promising in-situ hydrogen generation material, magnesium (Mg) has been seeking a promotion in its hydrogen generation property. Increasing the specific surface area, for example, replacing the Mg bulk using Mg powder, can greatly increase the hydrogen generation property, but it brings a high explosion risk, a difficulty in controlling the hydrogen generation, and an oxidation problem. In this work, we prepare a novel Mg@Ni foam material with Mg deposits on Ni foam by a physical vapor deposition method. The Ni foam not only increases the hydrolysis reaction areas of Mg by improving its specific surface area, but also kinetically accelerates the hydrolysis reaction rate of Mg by forming a uniform Mg-Ni galvanic cell. As a result, the Mg@Ni foam material realizes a near-theoretical hydrogen generation amount of Mg and a hydrogen generation rate significantly higher than those realized by the bulk Mg-based materials. The Mg@Ni foam material with the excellent hydrogen generation property is also free from explosion risk, easy to be controlled, and resistible to oxidation. A hydrogen fuel cell powered by the hydrogen generated by the Mg@Ni foam material can yield a steady voltage and run a small car for a long distance.

[Display omitted] Two-dimensional (2D) layered group-IV monochalcogenides with large surface-to-volume ratio and high surface activity make that their structural and optoelectronic properties are sensitive to air oxidation. Here, we report the utilization of oxidation-induced gradient doping to modulate electronic structures and optoelectronic properties of 2D group-IV monochalcogenides by using SnS nanoplates grown by physical vapor deposition as a model system. By a precise control of oxidation time and temperature, the structural transition from SnS to SnSO x could be driven by the layer-by-layer oxygen doping and intercalation. The resulting SnSO x with a graded narrowing bandgap exhibits the enhanced optical absorption and photocurrent, leading to the fabricated SnSO x photodetector with remarkable photoresponsivity and fast response speed (<64 μs) at a broadband spectrum range of 520–1550 nm. The peak responsivity (7294 A/W) and detectivity (9.54 × 109 Jones) of SnSO x device are at least two orders of magnitude larger than those of SnS photodetector. Moreover, its photodetection performance can be competed with state-of-the-art of 2D materials-based photodetectors. This work suggests that the air oxidation could be utilized as an efficient strategy to engineer the electronic and optical properties of SnS and other 2D group-IV monochalcogenides for the development of high-performance broadband photodetectors. [ABSTRACT FROM AUTHOR]

Recently, various methods have been developed for synthesizing zinc oxide (ZnO) nanostructures, including physical and chemical vapor deposition, as well as wet chemistry. These common methods require either high temperature, high vacuum, or toxic chemicals. In this study, we report the growth of zinc oxide ZnO nanowires by a new hot water deposition (HWD) method on various types of substrates, including copper plates, foams, and meshes, as well as on indium tin oxide (ITO)-coated glasses (ITO/glass). HWD is derived from the hot water treatment (HWT) method, which involves immersing piece(s) of metal and substrate(s) in hot deionized water and does not require any additives or catalysts. Metal acts as the source of metal oxide molecules that migrate in water and deposit on the substrate surface to form metal oxide nanostructures (MONSTRs). The morphological and crystallographic analyses of the source-metals and substrates revealed the presence of uniformly crystalline ZnO nanorods after the HWD. In addition, the growth mechanism of ZnO nanowires using HWD is discussed. This process is simple, inexpensive, low temperature, scalable, and eco-friendly. Moreover, HWD can be used to deposit a large variety of MONSTRs on almost any type of substrate material or geometry. [ABSTRACT FROM AUTHOR]

Recent advancements in organic materials based sensor technology created a prospective field in designing sensors that are both cost‐effective and environment friendly. In view of that an electronic material system has been prepared depositing a uniform layer of graphite‐infused Polyaniline (PANI) onto the sponge framework using a straightforward physical vapor deposition technique. The prepared active materials were studied for the composition, morphology, optical properties, and charge transport characteristics. In the current context of rapidly growing sensor technology, this works describes an innovative approach of improving the response of the prepared electronic system of PANI/Gr composites, integrated into porous PU sponge substrates. Incorporation of graphite in PANI improved the electrical conductivity of the composite and porous structure of PU increased the interaction surface area. The performance of the prepared materials in humidity detection was evaluated by studying their resistive response under varying humidity levels, which was measured through current‐voltage (I‐V) characteristics. The higher interaction sites of the reported active sensing system leads to inspiring humidity sensitivity of 0.522–26.22 kΩ/% RH with reasonable response and recovery time of 572 and 416 sec respectively. Additionally, the reported sensor system consisting of degradable materials will offer a useful way of reducing electronic garbage. [ABSTRACT FROM AUTHOR]

The tribological performance of the tungsten carbide substrate (WC‐Co), improved by ceramic coatings, is still being reported in new studies that have been carried out to date. It has become a hot research topic that are widely applied in hard material research, especially in the tools manufacturing fields. This study was conducted to investigate the wear characteristics of a commercial cemented carbide tool (WC‐Co) coated with a physical vapor deposition chromium‐vanadium nitride film (CrVN), followed by a boriding process as a final thermochemical treatment. Tested in dry sliding contact against an alumina ball as a static partner, the tribological responses of the specimen were analyzed and compared with an uncoated specimen. Friction coefficients, calculated from volume loss, were around.58 for all specimens except the uncoated specimen at 10 N of applied load. Wear scar analyses revealed the occurrence of several wear mechanisms that is polishing, oxidation, wear debris formation, surface binder removal, grain fragmenting, and grain pull‐out. [ABSTRACT FROM AUTHOR]

Films of dipolar molecules formed by physical vapor deposition are, in general, spontaneously polarized, with implications ranging from electron transfer in molecular optoelectronic devices to the properties of astrochemical ices in the interstellar medium. Polarization arises from dipole orientation, which should intuitively decrease with increasing deposition temperature, T. However, it is experimentally found that minimum or maximum values in polarization vs T may be observed for cis-methyl formate, 1-propanol, and ammonia. A continuous analytic form of polarization vs T is developed, which has the property that it is not differentiable at all T. The minima and maxima in polarization vs T are marked by singularities in the differential of this analytic form. This exotic behavior is presently unique to films of dipolar species and has not been reported, for example, in the related magnetic phases of spin glasses. [ABSTRACT FROM AUTHOR]

TiO2 thin films were prepared by sol-gel spin-coating (SGSC) and electron beam-physical vapor deposition (EB-PVD) methods and annealed at different temperatures (Ta). X-ray diffraction spectroscopy (XRD) results show that the TiO2 films prepared by the SGSC method transformed from the anatase single phase to the coexistence of anatase and rutile with the increase of Ta. However, TiO2 films prepared by the EB-PVD method existed only in the anatase phase, and the crystalline strength was enhanced with the increase of Ta. Meanwhile, particles of TiO2 targets annealed at different Ta showed a rutile phase for TiO2 target particles in the EB-PVD method. The results indicate that the EB-PVD method hinders the nucleation growth and phase transformation of TiO2 films. Scanning electron microscopy and atomic force microscopy also show that the grain size and R ms of TiO2 thin films prepared by the SGSC method increased with the increase of Ta, and the grain size becomes inhomogeneous when the rutile phase is formed. Ultraviolet–visible results show that the forbidden bandwidth and light absorption capacity increase with increasing Ta. For the EB-PVD method, the grain size and surface roughness gradually increased when the Ta of the films was less than 800 °C, while annealing at 800 °C changed the direction of growth and nucleation, and also produced surface cracks; XRD verified the hypothesis that the EB-PVD method hinders the nucleation growth as well as the phase transition of the films. Weak differences in the optical absorption properties and bandgap values of the films also indicate that the EB-PVD method hinders the phase transformation of TiO2 films. Finally, the results of degradation of methylene blue (MB) under simulated visible light showed that the films prepared by the SGSC method gradually improved the photocatalytic performance with the enhancement of the crystalline strength of the anatase phase. The TiO2 films prepared by the EB-PVD method improved the photocatalytic performance with the increase of the active area. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) and its alloys have received much attention in the aerospace, transportation, automotive industry, and military equipment fields due to their unique chemical and physical properties, such as their low density and high specific strength, particularly as the lightest structural metal materials, with the opportunity to achieve the design of lighter engineering systems. With the continuous improvement of processing technology, the application scope of magnesium alloy is rapidly expanding, and market demand is increasing. However, because of its significant electronegativity (2.37 V) and loose naturally formed oxide coating, magnesium has low corrosion resistance in comparison to other structural metal elements, severely limiting its large‐scale use. This review summarizes several typical anticorrosion methods for magnesium alloys, including chemical conversion coating treatment, anodic oxide film treatment, micro‐arc oxidation treatment, laser surface treatment, ion implantation, physical vapor deposition, and superhydrophobic coating. In most cases, the corrosion resistance of magnesium and its alloys has improved, but it has a certain degree of environmental damage. It is hoped that this review will contribute to further developing magnesium alloy materials in the field of preservative coating. [ABSTRACT FROM AUTHOR]

In this study, the surface characteristics of mild steel are modified using aluminum oxide (alumina) coating using the microwave‐assisted solution combustion synthesis (mSCS) and physical vapor deposition (PVD) technique. The deposited coatings are subjected to microstructural, X‐ray diffraction (XRD), micro‐hardness, surface roughness, high‐temperature oxidation, and wear tests. The XRD results confirmed the formation of α‐alumina coating on the mild steel surface. An average thickness of coatings is approximately 125 ± 5 µm in mSCS and around 1 ± .3 µm in PVD. The coating demonstrated good adherence and significantly improved surface hardness, wear resistance, and high‐temperature oxidation resistance. The surface hardness of coatings increased to 12.2 and 9.4 GPa from mSCS and PVD, respectively, while it is 1.57 GPa for the uncoated mild steel. The PVD‐coated alumina surface exhibited a smooth surface (Ra = .076 µm) compared to the mSCS coating (Ra = .344 µm). The specific wear rate of the alumina‐coated sample decreased to 2.5 times, and the high‐temperature oxidation rate decreased about 1.7 times at 500°C. [ABSTRACT FROM AUTHOR]

Mg is a research focus in the field of in-situ hydrogen generation due to its high activity, abundant reserves and mature circulation mode. However, the passivation issue of Mg bulks and the explosion risk of Mg powders hinder its practical application. In this work, we propose a novel nanoporous Mg-based material, whose nanoscale pores significantly reduce the passivation, and the self-supporting characteristic ensures its safe application. By co-depositing Mg–Zn and adjusting their ratios, three kinds of nanoporous Mg–Zn materials with different morphology and composition are obtained, that is, granular nanoporous (GNP) Mg–Zn, coral-like nanoporous (CNP) Mg–Zn and lotus root-like nanoporous (LNP) Mg–Zn materials. The GNP Mg–Zn material shows the best hydrogen generation performance among the three nanoporous Mg–Zn materials, and realizes an efficient and controllable hydrogen generation. The formation mechanism, the morphology evolution and the hydrogen generation mechanism of the nanoporous Mg–Zn materials are discussed in detail. [Display omitted] • Three nanoporous Mg–Zn materials have been prepared by co-depositing Mg and Zn. • Nanoporous structure and the Zn addition enhance the hydrogen generation property. • The formation mechanism of the nanoporous Mg–Zn material has been revealed. [ABSTRACT FROM AUTHOR]

Heterogeneous microstructures in Cu-Mo-W alloy thin films formed by magnetron co-sputtering immiscible elements with concentrated compositions are characterized using scanning transmission electron microscopy (STEM) and nanoindentation. In this work, we modified the phase separated structure of a Cu-Mo immiscible system by adding W, which impedes surface diffusion during film growth. The heterogeneous microstructures in the Cu-Mo-W ternary system exhibited bicontinuous matrices and agglomerates composed of Mo(W)-rich phase. This is unique, as these are the slower-diffusing species, contrasting past reports of binary Cu-Mo thin films that exhibited Cu-rich agglomerates. The bicontinuous matrices comprised of Cu-rich and Mo(W)-rich phases exhibited bilayer thicknesses of less than 5 nm. The hardness of these thin films measured using nanoindentation is reported and compared to similar multilayers and nanocomposites in binary systems. [ABSTRACT FROM AUTHOR]