Stabilizing 3D-printed metal alloys.

A design strategy overcomes the strength-ductility trade-off in alloy manufacturing.

Nanoscale Oxygenous Heterogeneity in FePC Glass for Highly Efficient and Reusable Catalytic Performance.

Metallic glass, with its unique disordered atomic structure and high density of low-coordination sites, is regarded as the most competitive new catalyst for environmental catalysis. However, the efficiency and stability of metallic glass catalysts are often affected by their atomic configuration. Thus, the design and regulation of the nanoscale structure of metallic glasses to improve their catalytic efficiency and stability remains a challenge.

The Role of Lithium in the Aging Precipitation Process of Al-Zn-Mg-Cu Alloys and Its Effect on the Properties.

It is well known that the development of lightweight alloys with improved comprehensive performance and application value are the future development directions for the ultra-high-strength 7xxx series Al-Zn-Mg-Cu alloys used in the aircraft field. As the lightest metal element in nature, lithium (Li) has outstanding advantages in reducing the density and increasing the elastic modulus in aluminum alloys, so Al-Zn-Mg-Cu alloys containing Li have gained widespread attention. Furthermore, since the Al-Zn-Mg-Cu alloy is usually strengthened by aging treatment, it is crucial to understand how Li addition affects its aging precipitation process.

Enhanced Hardness-Toughness Balance Induced by Adaptive Adjustment of the Matrix Microstructure in In Situ Composites.

With the development of high-speed and heavy-haul railway transportation, the surface failure of rail turnouts has become increasingly severe due to insufficient high hardness-toughness combination. In this work, in situ bainite steel matrix composites with WC primary reinforcement were fabricated via direct laser deposition (DLD). With the increased primary reinforcement content, the adaptive adjustments of the matrix microstructure and in situ reinforcement were obtained at the same time.

Defect Engineering of a High-Entropy Metallic Glass Surface for High-Performance Overall Water Splitting at Ampere-Level Current Densities.

Platinum-based electrocatalysts possess high water electrolysis activity and are essential components for hydrogen evolution reaction (HER). A major challenge, however, is how to break the cost-efficiency trade-off. Here, a novel defect engineering strategy is presented to construct a nanoporous (FeCoNiB ) Pt (atomic %) high-entropy metallic glass (HEMG) with a nanocrystalline surface structure that contains large amounts of lattice distortion and stacking faults to achieve excellent electrocatalytic performance using only 3 at% of Pt.

Cobalt oxide functionalized ceramic membrane for 4-hydroxybenzoic acid degradation via peroxymonosulfate activation.

Membrane separation and sulfate radicals-based advanced oxidation processes (SR-AOPs) can be combined as an efficient technique for the elimination of organic pollutants. The immobilization of metal oxide catalysts on ceramic membranes can enrich the membrane separation technology with catalytic oxidation avoiding recovering suspended catalysts. Herein, nanostructured CoO ceramic catalytic membranes with different Co loadings were fabricated via a simple ball-milling and calcination process.

Nanoscale Heterogeneities of Non-Noble Iron-Based Metallic Glasses toward Efficient Water Oxidation at Industrial-Level Current Densities.

Scaling up the production of cost-effective electrocatalysts for efficient water splitting at the industrial level is critically important to achieve carbon neutrality in our society. While noble-metal-based materials represent a high-performance benchmark with superb activities for hydrogen and oxygen evolution reactions, their high cost, poor scalability, and scarcity are major impediments to achieve widespread commercialization. Herein, a flexible freestanding Fe-based metallic glass (MG) with an atomic composition of FeNiPC was prepared by a large-scale metallurgical technique that can be employed directly as a bifunctional electrode for water splitting.

Multi-scale hybrid modified coatings on titanium implants for non-cytotoxicity and antibacterial properties.

Titanium and its alloys are among the widely used materials in the biomedical field, but they have poor wear resistance and antibacterial properties. In the present study, anodization, photo-reduction, and spin-coating technologies were integrated to prepare a hybrid modified coating for bio-inert titanium implants, having excellent comprehensive performance. The surface roughness of Ti-35Nb-2Ta-3Zr was specifically optimized by surface modification leading to improved wear resistance.

Design and perspective of amorphous metal nanoparticles from laser synthesis and processing.

Amorphous metal nanoparticles (A-NPs) have aroused great interest in their structural disordering nature and combined downsizing strategies (e.g. nanoscaling), both of which are beneficial for highly strengthened properties compared to their crystalline counterparts.

A Hydrogen-Initiated Chemical Epitaxial Growth Strategy for In-Plane Heterostructured Photocatalyst.

Integrating carbon nitride with graphene into a lateral heterojunction would avoid energy loss within the interlaminar space region on conventional composites. To date, its synthesis process is limited to the bottom-up method which lacks the targeting and homogeneity. Herein, we proposed a hydrogen-initiated chemical epitaxial growth strategy at a relatively low temperature for the fabrication of graphene/carbon nitride in-plane heterostructure.

Role of Boron in Enhancing Electron Delocalization to Improve Catalytic Activity of Fe-Based Metallic Glasses for Persulfate-Based Advanced Oxidation.

Metallic glasses (MGs) with superior catalytic performance have recently been recognized as attractive candidates for wastewater treatment. However, further improving their performance will require knowledge of how to precisely regulate their electronic structures via compositional control. Here, two Fe-based MGs (FeSiB and FeSiB) were prepared to compare how slightly altering boron content affected their electronic structure and catalytic performance.

High MB Solution Degradation Efficiency of FeSiBZr Amorphous Ribbon with Surface Tunnels.

The as spun amorphous (FeSiB)Zr (Zr0.5) and (FeSiB)Zr (Zr1) ribbons having a Fenton-like reaction are proved to bear a good degradation performance in organic dye wastewater treatment for the first time by evaluating their degradation efficiency in methylene blue (MB) solution. Compared to the widely studied (FeSiB)Zr (Zr0) amorphous ribbon for degradation, with increasing (Zr atomic content), the as-spun Zr0, Zr0.

Tailoring surface morphology of heterostructured iron-based Fenton catalyst for highly improved catalytic activity.

Due to the great limitation of glass forming ability, precisely controlling the chemical compositions of metallic glasses (MGs) still dramatically inhibits their widespread applications in wastewater remediation. Here, heterostructured catalysts were exploited by rapid annealing of Fe-based MGs and subsequent ball milling (BM) as advanced alternatives for amorphous counterparts in Fenton-like process. It was found that the surface characteristics tailored by ball milling enable more chemically active sites due to its enlarged specific surface area, surface defects and nanosized amorphous oxide layer that significantly enhance surface-catalyzed reaction in Fenton-like process.

Surface Functionalization of Biomedical Ti-6Al-7Nb Alloy by Liquid Metal Dealloying.

Surface functionalization is an effective approach to change the surface properties of a material to achieve a specific goal such as improving the biocompatibility of the material. Here, the surface of the commercial biomedical Ti-6Al-7Nb alloy was functionalized through synthesizing of a porous surface layer by liquid metal dealloying (LMD). During LMD, the Ti-6Al-7Nb alloy is immersed in liquid magnesium (Mg) and both materials react with each other.

Atomically thin heavy-metal-free ZnTe nanoplatelets formed from magic-size nanoclusters.

Atomically thin colloidal quasi-two-dimensional (2D) semiconductor nanoplatelets (NPLs) have attracted tremendous attention due to their excellent properties and stimulating applications. Although some advances have been achieved in Cd- and Pb-based semiconductor NPLs, research into heavy-metal-free NPLs has been reported less due to the difficulties in the synthesis and the knowledge gap in the understanding of the growth mechanism. Herein wurtzite ZnTe NPLs with an atomic thickness of about 1.

Dealloyed porous gold anchored by generated graphene sheets as high activity catalyst for methanol electro-oxidation reaction.

A novel one-step method to prepare the nanocomposites of reduced graphene oxide (RGO)/nanoporous gold (NPG) is realized by chemically dealloying an AlAu precursor. The RGO nanosheets anchored on the surface of NPG have a cicada wing like shape and act as both conductive agent and buffer layer to improve the catalytic ability of NPG for methanol electro-oxidation reaction (MOR). This improvement can also be ascribed to the microstructure change of NPG in dealloying with RGO.

Manganese oxide integrated catalytic ceramic membrane for degradation of organic pollutants using sulfate radicals.

Membrane separation and advanced oxidation processes (AOPs) have been respectively demonstrated to be effective for a variety of water and/or wastewater treatments. Innovative integration of membrane with catalytic oxidation is thus expected to be more competing for more versatile applications. In this study, ceramic membranes (CMs) integrated with manganese oxide (MnO) were designed and fabricated via a simple one-step ball-milling method with a high temperature sintering.

Resemblance in Corrosion Behavior of Selective Laser Melted and Traditional Monolithic β Ti-24Nb-4Zr-8Sn Alloy.

Distinct corrosion behavior was reported in multiphased titanium alloys prepared by additive manufacturing and by traditional technologies because of different phase constituents formed during processing. An open question is therefore raised: is there always different corrosion behavior of materials prepared by different methods? This work reports resemble corrosion behavior of selective laser melted and wrought single β-phase Ti-24Nb-4Zr-8Sn (Ti2448) in both NaCl solution and Hank's solution. The electrochemical measurements showed that both samples have close calculated polarization resistance and corrosion potential in NaCl solution, i.

Near-Net Forming Complex Shaped Zr-Based Bulk Metallic Glasses by High Pressure Die Casting.

Forming complex geometries using the casting process is a big challenge for bulk metallic glasses (BMGs), because of a lack of time of the window for shaping under the required high cooling rate. In this work, we open an approach named the "entire process vacuum high pressure die casting" (EPV-HPDC), which delivers the ability to fill die with molten metal in milliseconds, and create solidification under high pressure. Based on this process, various Zr-based BMGs were prepared by using industrial grade raw material.

Compelling Rejuvenated Catalytic Performance in Metallic Glasses.

Metallic glasses (MGs) with the metastable nature and random atomic packing structure have attracted large attention in the catalytic family due to their superior catalytic performance. In contrast, their crystalline counterparts are restricted by the highly ordered packing structure, fewer surface active sites, and crystallographic defects for catalytic activity. The uncertainty of the different catalytic mechanisms and the intrinsic characteristics correlated to MGs and their crystalline counterparts become a major impediment to promote their catalytic efficiencies and widespread applications.

Fe-based Metallic Glasses in Functional Catalytic Applications.

With an intrinsically disordered atomic structure and a widely tunable atomic constituent, metallic glasses (MGs) have been extensively studied as promising catalysts in different catalytic fields. Particularly, Fe-based MGs with high catalytic activity, relatively low material cost, and environmental friendly compatibility also emerge as advanced catalysts. This review systematically discusses the recent advances of Fe-based MGs in catalytic applications, including wastewater remediation based on reductive degradation by multicomponent Fe-based MGs, oxidative degradation by introduction of advanced oxidation processes (AOPs) and nanocrystallization applied in Fe-based MGs up to date, and renewable energy conversion, with purposes of revealing Fe-based MG catalysts in the further improvement of catalytic performance and exploiting their promising catalytic abilities in a widely catalytic field.

Spontaneous Formation of Noble- and Heavy-Metal-Free Alloyed Semiconductor Quantum Rods for Efficient Photocatalysis.

Quasi-1D cadmium chalcogenide quantum rods (QRs) are benchmark semiconductor materials that are combined with noble metals to constitute QR heterostructures for efficient photocatalysis. However, the high toxicity of cadmium and cost of noble metals are the main obstacles to their widespread use. Herein, a facile colloidal synthetic approach is reported that leads to the spontaneous formation of cadmium-free alloyed ZnS Se QRs from polydisperse ZnSe nanowires by alkylthiol etching.

Improved Corrosion Resistance on Selective Laser Melting Produced Ti-5Cu Alloy after Heat Treatment.

A Ti-5Cu alloy produced by selective laser melting exhibits a nonuniform TiCu phase structure, which contains a small amount of α' phase in melt pool boundaries thereby resulting in reduced corrosion resistance. The heat-treatment process proposed in this work eliminates the deleterious effect of α' phase and the TiCu phase is refined using different cooling rates, which improves the corrosion resistance. The electrochemical results indicate that the heat-treated Ti-5Cu samples have similar corrosion behavior to pure CP-Ti.

Nanocrystalline CoSe Anchored on Graphene Nanosheets as a Highly Efficient and Stable Electrocatalyst for Hydrogen Evolution Reaction.

For the first time, a porous and conductive CoSe/graphene network (CSGN), constructed by CoSe nanocrystals being tightly connected with each other and homogeneously anchored on few-layered graphene nanosheets, has been synthesized by a facile one-pot solvothermal method. Compared to unhybridized CoSe, CSGN exhibits much faster kinetics and better electrocatalytic behavior for hydrogen evolution reaction (HER). The HER mechanism of CSGN is improved to Volmer-Tafel combination, instead of Volmer-Heyrovsky combination, for CoSe.