Multicomponent Metal Research Articles

Effectiveness and mechanism for the simultaneous adsorption of Pb(II), Cd(II) and As(III) by animal-derived biochar/ferrihydrite composite

The emerging animal-derived biochar (AB) has shown potential for mitigating the contamination of cationic heavy metals, but has no affinity to oxyanionic metals. In this study, we developed an AB/ferrihydrite composite with a AB/Fe mass ratio of 4.0 (ABF-4) for the simultaneous adsorption of cationic Pb(II)/Cd(II) and anionic As(III). ABF-4 is a type of hydroxyapatite-rich biochar coated with nanoscale iron hydroxide aggregates. The adsorption of Pb(II), Cd(II), and As(III) on ABF-4 were 2.64, 1.55, and 0.48 mmol/g, and were 135%, 150%, and 4500% higher than those of pure AB, respectively. The enhanced adsorption of Pb(II) and Cd(II) by ABF-4 is partially due to the increase in surface area and micropores. The nano-sized ferrihydrite on ABF might help form surface complexation with As(III) and oxidize As(III) to As(V). In multimetal systems, Pb(II) and Cd(II) can promote As(III) adsorption due to the formation of NaPb4(AsO4)3 precipitate and the ternary complex of arsenite and cadmium with ABF-4, whereas Cd(II) adsorption might be inhibited because of the surface coverage of Pb5(PO4)3Cl precipitate on ABF-4. However, the coexistence of Pb in soils does not influence the immobilization of Cd. The amendment of ABF-4 can considerably decrease the availability of Pb, Cd, and As in soils from Pb–Zn smelting sites. Hence, ABF-4 is a promising multifunctional material for the potential immobilization of multicomponent heavy metals.

Boosting electrochemical reaction and suppressing phase transition with a high-entropy O3-type layered oxide for sodium-ion batteries

A high-entropy O3-type layered oxide cathode Na(Fe0.2Co0.2Ni0.2Ti0.2Sn0.1Li0.1)O2 with disordered distribution of multi-component transition metals suppresses the complex intermediate phase transition, enabling highly reversible electrochemical reaction.

Nio‐Co3o4‐Rgo as a Multi-Component Transition Metal Oxide Nanocatalyst for Ultra-Level Detection of Nitrite in Beef and Tap Water Samples

Nio‐Co3o4‐Rgo as a Multi-Component Transition Metal Oxide Nanocatalyst for Ultra-Level Detection of Nitrite in Beef and Tap Water Samples

Structure-engineering of core-shell ZnCo2O4@NiO composites for high-performance asymmetric supercapacitors.

The implementation of a structure-designed strategy to construct hierarchical architectures of multicomponent metal oxide-based electrode materials for energy storage devices is in the limelight. Herein, we report NiO nanoflakes impregnated on ZnCo2O4 nanorod arrays as ZnCo2O4@NiO core–shell structures on a flexible stainless-steel mesh substrate, fabricated by a simple, cost-effective and environmentally friendly reflux condensation method. The core–shell structure of ZnCo2O4@NiO is used as an electrode material in a supercapacitor as it provides a high specific surface area (134.79 m2 g−1) offering high electroactive sites for a redox reaction, reduces the electron and ion diffusion path, and promotes an efficient contact between the electroactive material and electrolyte. The binder-free ZnCo2O4@NiO electrode delivers a high specific capacitance of 882 F g−1 at 4 mA cm−2 current density and exhibits remarkable cycling stability (∼85% initial capacitance retention after 5000 charge–discharge cycles at 10 mA cm−2). The asymmetric supercapacitor device ZnCo2O4@NiO//rGO delivered a maximum energy density of 46.66 W h kg−1 at a power density of 800 W kg−1. The device exhibited 90.20% capacitance retention after 4000 cycles. These results indicate that the ZnCo2O4@NiO architecture electrode is a promising functional material for energy storage devices.

One-step solvent-free aerobic oxidation of aliphatic alcohols to esters using a tandem Sc–Ru⊂MOF catalyst

A multicomponent metal–organic framework-based catalyst has been developed for direct alcohol to ester conversion under solvent-free conditions.

Прогнозна оцінка фізико-хімічних властивостей нових композицій хромовмістних феросплавів

The aim of the work was to predict the most significant physicochemical characteristics (melting temperature and density) of new chromium-containing ferroalloys with reduced chromium content and increased silicon content. The applied methodology and criteria for quantitative assessment took into account microheterogeneity of multicomponent metal melts, melting temperature and density. Information about these characteristics is necessary for studying the kinetics of melting, assimilation of the leading elements of ferroalloys by the metal melt, and determining the efficiency of their use. An original approach is used to solve the modeling tasks, which is based on the concept of physicochemical modeling of interatomic interaction processes in melts, developed under the leadership of Professor E. V. Prykhodko. According to the developed concept, metal melts are considered as chemically unified systems, and a change in their composition affects a complex of physical and chemical properties caused by a change in the parameters of their electronic structure. To evaluate and take into account the influence of the microheterogeneity of the structure of melts of ferroalloy systems, the method of calculating criteria (ΔZy and Δd) was used, characterizing the degree of difference in the electronic and structural state of the melt as a chemically unified system, as opposed to a mechanical mixture of their initial components. Using these criteria and experimental ones, the values of the most important physicochemical characteristics of new compositions of chromium-containing ferroalloys, which are missing in the literature, were obtained. The results of the calculation of these properties can be used to change and improve the characteristics of chromium-containing ferroalloys in order to develop their rational compositions.

Artificial synapses based on layered multi-component metal oxides

Neuromorphic electronics has received considerable attention recent years, and its basic functional units are synaptic electronic devices. A two-terminal artificial synapse with sandwiched structure emulates plasticity of the biological synapses under the action of nerve-like electrical impulse signals. In this paper, <i>P</i>3 phase Na<sub>2/3</sub>Ni<sub>1/3</sub>Mn<sub>2/3</sub>O<sub>2</sub> multi-element metal oxides with layered structure are synthesized by sol-gel process. Owing to the fact that Na<sup>+</sup> is easy to embed/eject into its crystal structure, an ion-migrating artificial synapse based on Na<sub>2/3</sub>Ni<sub>1/3</sub>Mn<sub>2/3</sub>O<sub>2</sub> is designed and fabricated. The device emulates important synaptic plasticity, such as excitatory postsynaptic current, paired-pulse facilitation, spike-number dependent plasticity, spike-frequency dependent plasticity, spike-voltage amplitude dependent plasticity and spike-duration dependent plasticity. The device realizes the identification and response to Morse code commands.

Full-Color Emission in Multicomponent Metal–Organic Frameworks via Linker Installation

Herein, we demonstrate that linker installation (LI) through postsynthesis is an effective strategy to insert emissive second linkers into single-linker-based metal-organic frameworks (MOFs) to tune the emission properties of multicomponent MOFs. Full-color emission, including white-light emission, can be achieved via such a LI process.

High-Throughput Study of Antisolvents on the Stability of Multicomponent Metal Halide Perovskites through Robotics-Based Synthesis and Machine Learning Approaches.

Antisolvent crystallization methods are frequently used to fabricate high-quality metal halide perovskite (MHP) thin films, to produce sizable single crystals, and to synthesize nanoparticles at room temperature. However, a systematic exploration of the effect of specific antisolvents on the intrinsic stability of multicomponent MHPs has yet to be demonstrated. Here, we develop a high-throughput experimental workflow that incorporates chemical robotic synthesis, automated characterization, and machine learning techniques to explore how the choice of antisolvent affects the intrinsic stability of binary MHP systems in ambient conditions over time. Different combinations of the end-members, MAPbI3, MAPbBr3, FAPbI3, FAPbBr3, CsPbI3, and CsPbBr3 (MA, methylammonium; FA+, formamidinium), are used to synthesize 15 combinatorial libraries, each with 96 unique combinations. In total, roughly 1100 different compositions are synthesized. Each library is fabricated twice by using two different antisolvents: toluene and chloroform. Once synthesized, photoluminescence spectroscopy is automatically performed every 5 min for approximately 6 h. Nonnegative matrix factorization (NMF) is then utilized to map the time- and compositional-dependent optoelectronic properties. Through the utilization of this workflow for each library, we demonstrate that the selection of antisolvent is critical to the intrinsic stability of MHPs in ambient conditions. We explore possible dynamical processes, such as halide segregation, responsible for either the stability or eventual degradation as caused by the choice of antisolvent. Overall, this high-throughput study demonstrates the vital role that antisolvents play in the synthesis of high-quality multicomponent MHP systems.

Selective cobalt and nickel electrodeposition for lithium-ion battery recycling through integrated electrolyte and interface control

Molecularly-selective metal separations are key to sustainable recycling of Li-ion battery electrodes. However, metals with close reduction potentials present a fundamental challenge for selective electrodeposition, especially for critical elements such as cobalt and nickel. Here, we demonstrate the synergistic combination of electrolyte control and interfacial design to achieve molecular selectivity for cobalt and nickel during potential-dependent electrodeposition. Concentrated chloride allows for the speciation control via distinct formation of anionic cobalt chloride complex (CoCl42-), while maintaining nickel in the cationic form ([Ni(H2O)5Cl]+). Furthermore, functionalizing electrodes with a positively charged polyelectrolyte (i.e., poly(diallyldimethylammonium) chloride) changes the mobility of CoCl42- by electrostatic stabilization, which tunes cobalt selectivity depending on the polyelectrolyte loading. This strategy is applied for the multicomponent metal recovery from commercially-sourced lithium nickel manganese cobalt oxide electrodes. We report a final purity of 96.4 ± 3.1% and 94.1 ± 2.3% for cobalt and nickel, respectively. Based on a technoeconomic analysis, we identify the limiting costs arising from the background electrolyte, and provide a promising outlook of selective electrodeposition as an efficient separation approach for battery recycling.

Structural and Potential-Dependent Metal Anion Selectivity of Redox-Metallopolymer Electrosorbents

Selective electrochemically-mediated technologies for metal separations can be essential for materials recycling and environmental sustainability. Metal recovery not only requires selectivity of the target metal over the competing electrolyte, but also selectivity between metal ions of similar size and structure in order to sort metal ions for reuse and recycling. Ferrocene polymers have been shown to be highly selective for heavy metal oxyanions through charge transfer interactions.1 Using these polymers as electrosorbents provides the opportunity for highly tuned selectivity for different metal anions through modification of the polymer structure. We demonstrate a change in structure between a pendant group ferrocene polymer, polyvinylferrocene (PVF), and a main-chain ferrocene, polyferrocenylsilane (PFS), results in differential selectivity toward metal oxyanions.2 For example, almost an order of magnitude increase in separation factor for meta-vanadate over chromate (αVO3-,CrO42-) can be achieved by altering the polymer structure from PVF (αVO3-,CrO42- = 5.2) to PFS (αVO3-,CrO42- = 39) at 0.8 V vs Ag/AgCl. Through quantum chemical calculations, we elucidate how a trimethyl silane group attached to ferrocene affects charge transfer interactions between metal anions and ferrocene binding sites. In addition, we report that these ferrocene polymers exhibit potential dependent selectivity, and in some cases can even swap preference based on the applied potential, providing an additional process variable to tune selectivity that is orthogonal to structural modifications. The underlying cause of this potential dependent selectivity is undergoing further investigation. This work demonstrates the ability to tailor ferrocene polymer electrosorbents for the targeting of specific metal ions, and hints at potential applications in multicomponent separations, including metal valorization and environmental remediation. Su, X.; Kushima, A.; Halliday, C.; Zhou, J.; Li, J.; Hatton, T. A., Electrochemically-mediated selective capture of heavy metal chromium and arsenic oxyanions from water. Nature Communications 2018, 9 (1), 4701.Chen, R.; Feng, J.; Jeon, J.; Sheehan, T.; Rüttiger, C.; Gallei, M.; Shukla, D.; Su, X., Structure and Potential-Dependent Selectivity in Redox-Metallopolymers: Electrochemically Mediated Multicomponent Metal Separations. Advanced Functional Materials 2021, n/a (n/a), 2009307.

Biomarker responses in perch (Perca fluviatilis) under multiple stress: Parasite co-infection and multicomponent metal mixture exposure

Parasitic infections may cause damage to the host immune system (i.e. fish), thereby endangering its health and weakening its responses to other types of stressors. Therefore, exposure to different kinds of natural or anthropogenic stressors can lead to unexpected toxicity outcomes in aquatic organisms. This study examined the haematological, genotoxic and cytotoxic effects of the co-infection with the protozoan parasite (Trichodina sp.) and the pathogenic oomycete (Saprolegnia parasitica) in Perca fluviatilis alone and in combination with chemical stress (environmentally-relevant aqueous concentrations of metal mixtures). Haematological analyses such as red cell and white cell indices revealed that chemical and biological stressors, used singly and in combination, exerted adverse effects on fish health. Changes in haematological indices induced by exposure to each of the above-mentioned stressors separately and by combined exposure to all of them suggested the multiple stress-induced inflammation process in the exposed fish. The cytogenetic damage inflicted by the S. parasitica and Trichodina sp. co-infection and multiple stress was revealed in fish erythrocytes. This information is expected to contribute to the elucidation of how multiple stressors impact on responses of haematic indices, geno- and cytotoxicity endpoints in P. fluviatilis. Assessment of the risk associated with multiple stressors is expected to prove valuable for the effective aquatic environment management (Løkke et al., 2013 and references therein).

Vacuum brazing TiAl intermetallics to GH3030 alloy with a multi-component Ti-based filler metal

TiAl intermetallics was vacuum-brazed to GH3030 alloy with multi-component Ti-based amorphous filler metal (Ti 36.1 Zr 11.1 V 2.8 Cu 38.9 Ni 5.6 Al 2.8 Co 2.8 , at.%). The effect of brazing temperature on the microstructure evaluation and shear strength of TiAl/GH3030 brazed joint was studied. The brazed seam presented sectionalized feature with the formation of four reaction zones. Two transition zones with linear growth formed respectively adjacent to two base metals due to elemental solid-state diffusion from the filler metal to base metals. Increasing the brazing temperature accelerated the diffusion between the filler metal and base metals. And those two transition zones thickened, as well as the middle zone composed of primary phase and (Ti, Zr)(Al, Cu, Ni) matrix. Blocky primary phase Ti(Al, Cu, Ni) 3 in middle brazed seam increased, thinning the Ti(Ni, Cu) reaction layer. The maximum shear strength of the brazed joint was obtained at 990 °C. During the shear test, the cracks of the brazed joint propagated along the interface of the transition zone/middle brazed seam at TiAl base metal side on account of the stress concentration and the formation of Ti(Al, Cu, Ni) and Ti(Al, Cu, Ni) 3 at two sides of the fractured interface. And the failed joint exhibited layered fracture surfaces and brittle fracture feature.

ZnOHF/N-doped carbon hybrids as a novel anode material for enhanced lithium storage

Multicomponent transition metal compounds (TMCs) composed of many cations and anions have aroused widespread concern on account of their excellent electrochemical properties. Herein, the ZnOHF nanorod anchored to honeycomb-like N-doped porous carbon composite was successfully prepared through a hydrothermal method and used as a novel anode material in lithium-ion batteries (LIBs) for the first time. The specific structure can effectively improve the electronic conductivity, promote electrolyte penetration and accelerate lithium-ion diffusion. Therefore, the ZnOHF/N-C composite exhibits excellent initial discharge capacity (946.8 mAh g−1), high initial coulombic efficiency (ICE, 87.3%) and excellent cyclability (1050.2 mAh g−1 after 430 cycles). What's more, due to the high capacitance contribution of ZnOHF/N-C electrode, it has outstanding rate capability. This study provides a novel idea for the design of multi-component transition metal compound anode materials for LIBs.

Relationship between Kinematic Viscosity and Cluster Size in Multicomponent Metal Melts

We analyzed the temperature dependences of the kinematic viscosity and density of Fe73.5Cu1M3Si13.5B9 melts, where M = Nb, Mo, V, and Cr, in the temperature range from 1450 to 1950 K using the transition state theory. It is shown that the activation energy of viscous flow is proportional to the particle size on a natural logarithmic scale. The lowest viscosity and the highest free volume has the Nb melt. In melts with Mo, V, and Cr, the structural units of viscous flow upon heating and cooling are clusters about 0.6 nm in size. In a melt with Nb, at the initial stage of heating, the vibrations of individual atoms prevail, the movement of which creates viscosity. After heating the Nb melt above the critical temperature of 1770 K, the viscous flow is associated with clusters about 1 nm in size. At the cooling stage, the cluster structure of the Nb melt is retained up to a temperature of 1450 K.

Controlling the optical properties of nanostructured oxide-based polymer films

A bulk scale process is implemented for the production of nanostructured film composites comprising unary or multi-component metal oxide nanoparticles dispersed in a suitable polymer matrix. The as-received nanoparticles, namely Al_2O_3, SiO_2 and TiO_2 and binary combinations, are treated following specific chemical and mechanical processes in order to be suspended at the optimal size and composition. Subsequently, a polymer extrusion technique is employed for the fabrication of each film, while the molten polymer is mixed with the treated metal oxide nanoparticles. Transmission and reflection measurements are performed in order to map the optical properties of the fabricated, nanostructured films in the UV, VIS and IR. The results substantiate the capability of the overall methodology to regulate the optical properties of the films depending on the type of nanoparticle formation which can be adjusted both in size and composition.

Construction of CuII Defects on CuCl Nanoparticles in Metal-Organic Frameworks toward Composite Catalysts with Superior Activity.

Metal-organic frameworks (MOFs) represent an ideal platform for the construction of highly active composite catalysts. However, loading metastable and/or multicomponent metal compounds into MOFs remains a synthetic bottleneck due to the great challenge of keeping the guest and matrix intact during the preparation of a composite. In this work, we develop a new impregnation reduction surface modification (IRSM) strategy to give a new composite catalyst CuCl@MIL-101(Cr), which is successfully postmodified by in situ construction of CuII defects on the surface of loaded CuCl inside MOF pores, leading to the new composite material CuII/CuI@MIL-101(Cr). The new dual-component composite catalyst exhibits a hierarchical structure and superior catalytic activity in C-C homocoupling of arylboronic acids under green conditions. This study presents a facile strategy for improving the catalytic activity by constructing defects on the surface of MOF-based catalysts as well as for forming multiple-component composite materials.

Mixed transition-metal oxides@carbon core-shell nanostructures derived from heterometallic clusters for enhanced lithium storage

Multicomponent binary metal oxide-involved hybrid structures with unique physicochemical properties have received extensive attention due to their fascinating electrochemical performance. Herein, a flexible strategy, which involves the preparation of dual-functional heterometallic Fe2M clusters and their subsequent sintering treatment, is developed to engineer novel 3D hierarchical porous structures assembled with MFe2O4 (M = Co, Mn, Ni and Zn) nanoparticles confined within carbon outer shell (denoted as MFe2O4@C HPSs). In this intriguing construction, it can be observed that MFe2O4@C HPSs comprised of carbon coated secondary MFe2O4 nanoparticles with an interconnected carbon network. The as-prepared MFe2O4@C HPSs possess combined advantages of high capacity of MFe2O4 and high conductivity of carbon. As expected, the MFe2O4@C HPSs offer a high reversible capacity, high cycling stability and superior rate performance. The interconnected conductive carbon shells facilitates fast ion and electron transport and accommodates the mechanical strain. In addition, nanosized MFe2O4 particles, which shorten the ion-transport path and provide extra electroactive sites, also improve the reaction kinetics. Moreover, these MFe2O4@C HPSs exhibit good structural integrity during repeated charging and discharging. The research perspective and strategy reported here are highly versatile and shed new light on the synthesis of other advanced electrode for various applications.

Ni-Co-LDH and Zn-Co Prussian blue analogue derived hierarchical NiCo2O4@ZnO/ZnCo2O4 microspheres with enhanced electrochemical sensing performance towards pentachloronitrobenzene

In this work, we developed a hierarchical structure and multi-component synergistic metal oxide hybrid material, and explored its practical application in monitoring pentachloronitrobenzene (PCNB). We used the ZnO/ZnCo2O4, obtained by calcining Zn-Co Prussian blue analogue (PBA), as the substrate and integrated Ni-Co layered double hydroxide (LDH) on its surface and calcined to obtain hierarchical NiCo2O4@ZnO/ZnCo2O4 microspheres (MSs). Due to the p-n heterojunction characteristics of p-type semiconductor NiCo2O4 and ZnCo2O4 and n-type semiconductor ZnO and the high specific surface area of the microspheres supported by the hierarchical structure conductive network, when this material was used to modify the glassy carbon electrode (GCE), it significantly enhanced the electrochemical sensing performance towards PCNB. Therefore, a new type of electrochemical sensor was constructed based on NiCo2O4@ZnO/ZnCo2O4 MSs and molecularly imprinted polymer (MIP) for the sensitive and highly selective detection of PCNB. Among them, the MIP membrane was fabricated by cyclic voltammetry (CV), and differential pulse voltammetry (DPV) was used to detect PCNB. Under the optimum conditions, the reduction peak current density of PCNB was linearly related to the concentration from 0.05 to 5.5 μM with a detection limit of 8.33 nM and a good sensitivity of 6.118 μA⋅μM−¹⋅cm−². Furthermore, the proposed MIP sensor exhibited high selectivity, reproducibility, repeatability, and stability, and had been used for the detection of PCNB residues in licorice, river water, and soil samples with satisfactory results.

In-situ reconstruction of non-noble multi-metal core-shell oxyfluorides for water oxidation

The electrochemical anodic behavior of transition metal compounds plays an undeniably non-negligible role across many electrooxidation reactions. In this work, a chronopotentiometric technique was employed to activate the multicomponent non-noble metal oxyfluorides in-situ for oxygen evolution reaction (OER). It is interesting to unravel that the increasing applied current density helps to reconstruct the catalyst into nanoporous core–shell structure and introduce metal oxyhydroxide on the surface, which guarantees more channels for efficient ion/mass transportation and thus contributes to exposing more active sites for catalytic reaction. The activated five-membered oxyfluoride shows the best catalytic activity with overpotential of 348 ± 2 mV to achieve the current density of 10 mA/cm2 and a Tafel slope of 110.3 ± 0.1 mV/dec, in contrast with the pristine one (532 ± 2 mV & 240.2 ± 0.1 mV/dec). It still maintains high stability after long time OER measurement, making it a promising succedaneum for noble metal catalysts. The high-entropy effect, amorphous state and high active sites density jointly contribute to its enhanced OER performance. This work provides new ideas for realizing the potential of inactive elements via entropy engineering and using electrochemical self-reconstruction to modify semiconductors for advanced water oxidation.