Multicomponent Nanoparticles Research Articles

Cobalt-based multicomponent nanoparticles supported on N-doped graphene as advanced cathodic catalyst for zinc—air batteries

Cobalt-based multicomponent nanoparticles supported on N-doped graphene as advanced cathodic catalyst for zinc—air batteries

Synthesis of Complex Concentrated Nanoparticles by Ultrasonic Spray Pyrolysis and Lyophilisation

The development of new multicomponent nanoparticles is gaining increasing importance due to their specific functional properties, i.e., synthesised new complex concentrated nanoparticles (CCNPs) in the form of powder using ultrasonic spray pyrolysis (USP) and lyophilisation from the initial cast Ag20Pd20Pt20Cu20Ni20 alloy, which was in the function of the material after its catalytic abilities had been exhausted. Hydrometallurgical treatment was used to dissolve the cast alloy, from which the USP precursor was prepared. As a consequence of the incomplete dissolution of the cast alloy and the formation of Pt and Ni complexes, it was found that the complete recycling of the alloy is not possible. A microstructural examination of the synthesised CCNPs showed that round and mostly spherical (not 100%) nanoparticles were formed, with an average diameter of 200 nm. Research has shown that CCNPs belong to the group with medium entropy characteristics. A mechanism for the formation of CCNPs is proposed, based on the thermochemical analysis of element reduction with the help of H2 and based on the mixing enthalpy of binary systems.

Kinetically Programming Copolymerization-like Coassembly of Multicomponent Nanoparticles with DNA.

Programmable coassembly of multicomponent nanoparticles (NPs) into heterostructures has the capability to build upon nanostructured metamaterials with enhanced complexity and diversity. However, a general understanding of how to manipulate the sequence-defined heterostructures using straightforward concepts and quantitatively predict the coassembly process remains unreached. Drawing inspiration from the synthetic concepts of molecular block copolymers is extremely beneficial to achieve controllable coassembly of NPs and access mesoscale structuring mechanisms. We herein report a general paradigm of kinetic pathway guidance for the controllable coassembly of bivalent DNA-functionalized NPs into regular block-copolymer-like heterostructures via the stepwise polymerization strategy. By quantifying the coassembly kinetics and structural statistics, it is demonstrated that the coassembly of multicomponent NPs, through directing the specific pathways of prepolymer intermediates, follows the step-growth copolymerization mechanism. Meanwhile, a quantitative model is developed to predict the growth kinetics and outcomes of heterostructures, all controlled by the designed elements of the coassembly system. Furthermore, the stepwise polymerization strategy can be generalized to build upon a great variety of regular nanopolymers with complex architectures, such as multiblock terpolymers and ladder copolymers. Our theoretical and simulation results provide fundamental insights on quantitative predictions of the coassembly kinetics and coassembled outcomes, which can aid in realizing a diverse set of supramolecular DNA materials by the rational design of kinetic pathways.

MOFs-Derived Three-Phase Microspheres: Morphology Preservation and Electromagnetic Wave Absorption.

Reasonable structural design and composition control are the dominant factors for tuning the electromagnetic absorbing properties of materials. In this paper, microspheres composed of NiO, Ni, and Co3O4 nanoparticles (NCMO) were successfully synthesized using a mild oxidation method. Benefiting from the multi-component composition and a unique microstructure, the RLmin of CNMO can reach −46.8 dB at 17 GHz, with an effective absorption bandwidth of 4.1 GHz (13.9–18 GHz). The absorbing properties and the absorbing mechanism analysis showed that the microsphere-structured NCMO composed of multi-component nanoparticles enhanced the interface polarization, thereby improving the absorption performance. This research provides a new avenue for MOF-derived oxide materials with excellent electromagnetic wave absorbing properties.

Computational Reverse-Engineering Analysis for Scattering Experiments (CREASE) with Machine Learning Enhancement to Determine Structure of Nanoparticle Mixtures and Solutions.

We present a new open-source, machine learning (ML) enhanced computational method for experimentalists to quickly analyze high-throughput small-angle scattering results from multicomponent nanoparticle mixtures and solutions at varying compositions and concentrations to obtain reconstructed 3D structures of the sample. This new method is an improvement over our original computational reverse-engineering analysis for scattering experiments (CREASE) method (ACS Materials Au2021, 1 (2 (2), ), 140−156), which takes as input the experimental scattering profiles and outputs a 3D visualization and structural characterization (e.g., real space pair-correlation functions, domain sizes, and extent of mixing in binary nanoparticle mixtures) of the nanoparticle mixtures. The new gene-based CREASE method reduces the computational running time by >95% as compared to the original CREASE and performs better in scenarios where the original CREASE method performed poorly. Furthermore, the ML model linking features of nanoparticle solutions (e.g., concentration, nanoparticles’ tendency to aggregate) to a computed scattering profile is generic enough to analyze scattering profiles for nanoparticle solutions at conditions (nanoparticle chemistry and size) beyond those that were used for the ML training. Finally, we demonstrate application of this new gene-based CREASE method for analysis of small-angle X-ray scattering results from a nanoparticle solution with unknown nanoparticle aggregation and small-angle neutron scattering results from a binary nanoparticle assembly with unknown mixing/segregation among the nanoparticles.

Electrochemical Investigation of Porosity in Core-Shell Magnetoplasmonic Nanoparticles.

Porous core-shell nanoparticles (NPs) have emerged as a promising material for broad ranges of applications in catalysts, material chemistry, biology, and optical sensors. Using a typical Ag core-Fe3O4 shell NP, a.k.a., magnetoplasmonic (MagPlas) NP, two porous shell models were prepared: i.e., Ag@Fe3O4 NPs and its SiO2-covered NPs (Ag@Fe3O4@SiO2). We suggested using cyclic voltammetry (CV) to provide unprecedented insight into the porosity of the core-shell NPs caused by the applied potential, resulting in the selective redox activities of the core and porous shell components of Ag@Fe3O4 NPs and Ag@Fe3O4@SiO2 NPs at different cycles of CV. The porous and nonporous core-shell nanostructures were qualitatively and quantitatively determined by the electrochemical method. The ratio of the oxidation current peak (μA) of Ag to Ag+ in the porous shell to that in the SiO2 coated (nonporous) shell was 400:3.2. The suggested approach and theoretical background could be extended to other types of multicomponent NP complexes.

Synthesizing multicomponent AlCrFeCuNi nanoparticles by joint electrical explosion of wires

For the first time, by the example of an AlCrFeCuNi alloy this research work shows the possibility of obtaining multicomponent metal nanoparticles using joint electrical explosion of wires made of different metals/alloys. The analysis of the structural-phase state of nanoparticles has shown that particles have lognormal distribution by size, and their number average size is 40 nm. The nanocrystalline structure of nanoparticles is represented by two phases based on BCC and FCC lattices. According to the research findings, joint electrical explosion of wires made of different metals and alloys is a promising technique for obtaining multicomponent metal nanoparticles.

From quaternary to senary high entropy antimonide nanoparticles by a facile and scalable thermal treatment method

Transition metal antimonides form a class of intermetallic compounds, which has drawn considerable attention due to their potential applications in various fields. However, the formation of nanostructures containing multiple transition metal elements has been a challenge. Here, a new class of multicomponent antimonide nanoparticles with chemical composition ranging from quaternary to senary were synthesized via a simple, reproducible, and scalable thermal treatment method. This method allows uniform elemental distributions in a single nanoparticle, demonstrating the ability to obtain medium- and high-entropy antimonide nanostructures. The mechanism of formation was proposed and the characteristics of obtained nanoparticles were investigated by X-ray diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. Under the achieved optimal synthesis conditions, the formation of a single-phase with a hexagonal structure (P63/mmc) was observed for the quaternary and quinary samples, whereas in the case of the senary samples, a trace of minor impurity can be observed.

Effect of the morphology and composition of trimetallic PtCuAu/C catalysts on the activity and stability of the methanol oxidation reaction

A study on the influence of the method for obtaining trimetallic PtCuAu/C catalysts on their activity in the oxidation of methanol has been carried out. The structural characteristics of the obtained trimetallic catalysts have been studied by X-ray diffraction and transmission electron microscopy. The nanoparticles of the material obtained by the galvanic synthesis method had a size twice as large (~ 6 nm) than the nanoparticles of the material obtained by the co-deposition of metal precursors. According to the results from the accelerated stress testing of catalysts, it was found that the material obtained by the galvanic method of substitution of copper atoms with gold had a higher residual activity in the oxidation of methanol than the commercial Pt/C analogue. This study shows the potential of obtaining and using multicomponent platinum-containing nanoparticles deposited on a carbon carrier as effective catalysts for use in methanol fuel cells.

Iron-Gold Nanoflowers: A Promising Tool for Multimodal Imaging and Hyperthermia Therapy.

The development of nanoplatforms prepared to perform both multimodal imaging and combined therapies in a single entity is a fast-growing field. These systems are able to improve diagnostic accuracy and therapy success. Multicomponent Nanoparticles (MCNPs), composed of iron oxide and gold, offer new opportunities for Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) diagnosis, as well as combined therapies based on Magnetic Hyperthermia (MH) and Photothermal Therapy (PT). In this work, we describe a new seed-assisted method for the synthesis of Au@Fe Nanoparticles (NPs) with a flower-like structure. For biomedical purposes, Au@Fe NPs were functionalized with a PEGylated ligand, leading to high colloidal stability. Moreover, the as-obtained Au@Fe-PEG NPs exhibited excellent features as both MRI and CT Contrast Agents (CAs), with high r2 relaxivity (60.5 mM−1⋅s−1) and X-ray attenuation properties (8.8 HU mM−1⋅HU). In addition, these nanoflowers presented considerable energy-to-heat conversion under both Alternating Magnetic Fields (AMFs) (∆T ≈ 2.5 °C) and Near-Infrared (NIR) light (∆T ≈ 17 °C). Finally, Au@Fe-PEG NPs exhibited very low cytotoxicity, confirming their potential for theranostics applications.

Shape-Changing DNA-Linked Nanoparticle Films Dictated by Lateral and Vertical Patterns.

The self-assembly of nanoscale building blocks into complex nanostructures with controlled structural anisotropy can open up new opportunities for realizing active nanomaterials exhibiting spatiotemporal structural transformations. Here, a combination of bottom-up DNA-directed self-assembly and top-down photothermal patterning is adopted to fabricate free-standing nanoparticle films with vertical and lateral heterogeneity. This approach involves the construction of multicomponent plasmonic nanoparticle films by DNA-directed layer-by-layer (LbL) self-assembly, followed by on-demand lateral patterning by the direct photothermal writing method. The distinct plasmonic properties of nanospheres and nanorods constituting the multidomain films enable photopatterning in a selective domain with precisely controlled vertical depths. The photopatterned films exhibit complex morphing actions instructed by the lateral and vertical patterns inscribed in the film as well as the information carried in DNA.

Towards Multicomponent Intermetallic Nanoparticles as Efficient and Low-Cost Catalysts

Towards Multicomponent Intermetallic Nanoparticles as Efficient and Low-Cost Catalysts

On transformations of systems of integral equations for a multicomponent nano particle lying on a deformable layer under vibration conditions

On transformations of systems of integral equations for a multicomponent nano particle lying on a deformable layer under vibration conditions

Morphological, electronic, and magnetic properties of multicomponent cobalt oxide nanoparticles synthesized by high temperature arc plasma

Many technological applications demand large amount of nanoparticles with well-defined properties, which is feasible only by using large-scale production methods. In this framework, we have performed structural and local geometric investigations of cobalt oxide nanoparticles synthesized by high temperature arc plasma route in helium and in air atmosphere with different arc currents, a competitive and low cost technological approach to synthesize large quantity of different types of nanoparticles. The complex scenario of phase fraction, shape, size distribution and hysteresis loop features of high temperature arc plasma synthesis of nanoparticles can be determined by the arc current and the selected gas. X-ray diffraction patterns reveal a multicomponent phase formation containing cubic cobaltous oxide (CoO), cobaltic oxide (Co3O4) and metallic cobalt phases. The synthesis of different phases is confirmed by x-ray absorption spectroscopy measurements at the Co K-edge. Both extended x-ray absorption fine structure and x-ray absorption near edge structure analyses show the presence of metallic nanoparticles in He ambient at high arc current. Moreover, high-resolution transmission electron microscopy images and magnetic hysteresis loop measurements show that the mean particle size increases and the coercivity decreases with increasing arc current in air ambient due to the intense particle–particle interaction. At variance, in He ambient synthesized samples due to the high quenching rate and the high thermal conductivity, a multi-domain formation in which the nanoparticles’ crystalline fraction decreases and a fluctuating coercivity due to core–shell structure is observed.

A versatile multicomponent mesoporous silica nanosystem with dual antimicrobial and osteogenic effects

In this manuscript, we propose a simple and versatile methodology to design nanosystems based on biocompatible and multicomponent mesoporous silica nanoparticles (MSNs) for infection management. This strategy relies on the combination of antibiotic molecules and antimicrobial metal ions into the same nanosystem, affording a significant improvement of the antibiofilm effect compared to that of nanosystems carrying only one of these agents. The multicomponent nanosystem is based on MSNs externally functionalized with a polyamine dendrimer (MSN-G3) that favors internalization inside the bacteria and allows the complexation of multiactive metal ions (MSN-G3-Mn+). Importantly, the selection of both the antibiotic and the cation may be done depending on clinical needs. Herein, levofloxacin and Zn2+ ion, chosen owing to both its antimicrobial and osteogenic capability, have been incorporated. This dual biological role of Zn2+ could have and adjuvant effect thought destroying the biofilm in combination with the antibiotic as well as aid to the repair and regeneration of lost bone tissue associated to osteolysis during infection process. The versatility of the nanosystem has been demonstrated incorporating Ag+ ions in a reference nanosystem. In vitro antimicrobial assays in planktonic and biofilm state show a high antimicrobial efficacy due to the combined action of levofloxacin and Zn2+, achieving an antimicrobial efficacy above 99% compared to the MSNs containing only one of the microbicide agents. In vitro cell cultures with MC3T3-E1 preosteoblasts reveal the osteogenic capability of the nanosystem, showing a positive effect on osteoblastic differentiation while preserving the cell viability. STATEMENT OF SIGNIFICANCE: A simple and versatile methodology to design biocompatible and multicomponent MSNs based nanosystems for infection management is proposed. These nanosystems, containing two antimicrobial agents, levofloxacin and Zn2+, have been synthetized by external functionalization of MSNs with a polycationic dendrimer (MSNs-G3), which favours its internalization inside the bacteria and lead the complexation with metal ions through the amines of the dendrimer. The nanosystems offer a notable improvement of the antibiofilm effect (above 99%) than both components separately as well as osteogenic capability with positive effect on the osteoblastic differentiation and preserved cell viability.

The preparation of mono- and multicomponent nanoparticle aggregates with layer-by-layer structure using emulsion templating method in microfluidics

We report on the preparation of multicomponent hollow aggregates by an emulsion templating method adapted to microfluidic format. The method exploits partial miscibility of aqueous colloidal solutions as discrete phase and n-butanol as continuous phase. The aggregates consisted of an inner inorganic shell composed of iron oxide (IO) and gold nanoparticles (Au NPs) covered with polycaprolactone (PCL) NPs. The aggregates of smaller sizes were prepared compared to immiscible phases due to the diffusion-controlled shrinkage of aqueous droplets. The aggregate surface properties were controlled by using different mobilities and affinities of IO, Au, and PCL NPs to the water:n-butanol interface. The biocompatible surface layer enclosing an inorganic shell with a core space for possible cargo loading endowed these constructs with properties appreciated in medicinal applications. A computational fluid dynamics model enabled the prediction of the droplet size and formation frequency together with flow field properties at the point of droplet detachment.

Galvanic Transformation Dynamics in Heterostructured Nanoparticles

AbstractCorrosion is a significant problem for the stability of structural metals and potentially for functional nanomaterials in operating environments. When two metals with different electrochemical potentials form a junction, galvanic corrosion occurs, resulting in the sacrificial dissolution of the metal with a higher oxidation potential (lower electrode potential). Here, it is shown that bimetallic hetero‐nanostructures composed of phase‐segregated metals undergo galvanic corrosion in aqueous environments. Such selective etching of the sacrificial metal in heterojunction particles leads to the formation of unusual and kinetically stabilized half‐spheroid particles. By using a fluid cell and in situ scanning transmission electron microscopy, a two‐stage corrosion process can be observed where the Cu experiences a fractal breakdown before the Ag corrodes due to the lack of a protective oxide layer. However, when treated with a mild Ar plasma, the stability of these structures against corrosion is enhanced due to the conversion of the amorphous native oxide to a denser, thin layer of CuO on the Cu surface. Taken together, this work highlights the importance of considering the effects of galvanic corrosion on the stability of multicomponent nanoparticles, and it shows how mass transport in a nanoscale system is influenced by redox processes.

Preparation and Characterization of Electrosprayed Nanoparticles containing Ethyl Maltol Flavor

In this study, electrospraying is used to prepare electrosprayed multicomponent nanoparticles of ethylcellulose and stearic acid entrapping ethyl maltol. Electrospraying nanoparticles produced were ≤100 nm diameter and narrow size distribution (polydispersity index 0.26) is achieved. The ethyl maltol entrapment efficiency and yield were approximately 88% and 76%, respectively. The presence of ethyl maltol flavor within the polymeric electrosprayed nanoparticles was shown by Fourier transform infrared spectroscopy. The morphology of the electrosprayed multicomponent nanoparticles generated was studied by transmission electron microscopy.

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.

Retention of heavy metals from mine tailings using Technosols prepared with native soils and nanoparticles

A large number of heavy metals are generated in tailings of precious metal extractive operations, which could cause high levels of water contamination. Because of the environmental and health concerns, many conventional technologies have been applied to capture heavy metals from mining-polluted streams with limited performance in terms of effectiveness and immobilization efficiency. In this context, this study evaluates the retention of mine-generated heavy metals using Technosols prepared with iron-rich soils and multicomponent nanoparticles of Fe/FeS (MCNPs). Firstly, nanoparticles were synthesized using orange-peel extract and sodium borohydride (NaBH4) as reductant agents and FeCl3.6H2O and Na2SO4 as metal precursors. The TEM and SEM images showed nanoparticles with roughly spherical morphology with a size in the range of 35.9 ± 11.7 nm arranged in a kind of filamentous structure. Secondly, Soils were dosed with 1% and 3% (w/w) of multicomponent nanoparticles and then used to capture heavy metals present in mine tailings using batch and fixed-bed column tests. The Technosol prepared with 97% soil, and 3% MCNPs reached on average 70% retention of heavy metals for fixed-bed setups. While, in batch experiments using the same Technosol, the capture of heavy metals was 80% after 6 min of treatment, and upon reaching 30 min, 90% removal was attained. This suggests that tailored Technosols might be part of a promising technology to treat contaminated mine tailings with reasonable spending.