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A new strategy is described for synthesizing nanostructures of transition metal phosphides, which has used the conversion of preformed metal nanoparticles into metal phosphides by solution-mediated reaction with trioctyphosphine (TOP). The results have shown that in addition to its utility for accessing transition metal phosphides using a highly robust method, various aspects of nanostructure can be influenced by controlling critical aspects of the metal nanoparticle precursors.

The example of hollow magnetic CoPt nanopheres synthesized through a novel and potentially general one-pot reaction that exploits an in situ sacrificial template is reported. One of the important implications of the successful synthesis of hollow nanospheres of a CoPt allow phase is that the alloy system have received much less synthetic development than single-metal systems.

The study demonstrated that metal nanoparticles could be used as a robust solution-based toolkit for synthesizing intermetallic compounds and alloys within minutes at low temperatures. The strategy exploits the enhanced reactivity and nanoscale diffusion distances afforded by binary nanoparticle composites to eliminate the need for high-temperature heating and atomic-scale homogenization, which are necessary using traditional methods for solid-state synthesis.

The article reports on the low-temperature solution synthesis of the non-equilibrium ordered intermetallic compounds with iron, golf, copper and nickel as nanocrystals. The intermetallic compounds have been observed via interfacial diffusion, coevaporation and ion beam manipulation. The synthesis was modified and the product isolated by adding ethanol and then extracting into the toluene layer of a toluene/water mixture.

Iron phosphide (FeP) nanoparticles have excellent properties such as fast charge transfer kinetics, high electrical conductivity, and high stability, making them a promising catalyst for hydrogen evolution reaction (HER). A challenge to the wide use of iron phosphide nanomaterials for this application is the available synthesis protocols that limit control over the resulting crystalline phase of the product. In this study, we report a method for synthesizing FeP through a solution-based process. Here, we use iron oxyhydroxide (β-FeOOH) as a cost-effective, environmentally friendly, and air-stable source of iron, along with tri- n -octylphosphine (TOP) as the phosphorus source and solvent. FeP is formed in a nanobundle morphology in the solution phase reaction at a temperature of 320 °C. The materials were characterized by pXRD and transmission electron microscopy (TEM). The optimization parameters evaluated to produce the phosphorus-rich FeP phase included the reaction rate, time, amount of TOP, and reaction temperature. Mixtures of Fe 2 P and FeP phases were obtained at shorter reaction times and slow heating rates (4.5 °C /min), while longer reaction times and faster heating rates (18.8 °C/min) favored the formation of phosphorus-rich FeP. Overall, the reaction lever that consistently yielded FeP as the predominant crystalline phase was a fast heat rate., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

We report a solution-based synthetic method to produce shape-tunable iron pyrite (FeS 2 ) nanocrystals using iron oxy-hydroxide (β-FeOOH) as a precursor and their application for selective reduction of functionalized nitroarenes to aniline derivatives with formic acid-triethylamine (HCOOH-Et 3 N) as a hydrogen donor system., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

In this study, we report a unique strategy that utilizes ZnO and ZnS microparticles and rods as fire-retardant materials when coated onto cotton fabrics. ZnO and ZnO/ZnS microparticles or rods were grown or adsorbed to the surface of cotton fibers. Properties such as heat release rate, total smoke release, and mass loss rate of the materials were tested using a cone calorimeter. ZnO and ZnO/ZnS rods were able to reduce the heat release rate and total smoke release from 118 kW/m 2 and 18.3 m 2 /m 2 to about 70.0 kW/m 2 and 6.00 m 2 /m 2 , respectively. The maximum average rate of heat emission and fire growth rate index, which is used to evaluate the fire spread rate, the size of the fire, and the propensity of fire development, were improved with these coatings and indicate that there are potential applications of these materials as fire retardants., Competing Interests: The authors declare no competing financial interest.

Nanobiomaterials are introducing new capabilities to coordinate cell selection, growth, morphology, and differentiation. Herein, we report that tuning the geometry of ordered arrays of nanopillars (NP) elicits specialized morphologies in adherent cells. Systematic analysis of the effects of the NP radius, height, and spacing reveals that stem cells assume either flattened, polarized, or stellate morphologies in direct response to interpillar spacing. Notably, on NPs of pitch near a critical spacing (d(crit) ≈ 2 μm for C3H10T1/2 cells), cells exhibit rounding of the cell body, pronounced polarization, and extension of narrow axon-like cell projections aligned with the square lattice of the NP array and extending hundreds of micrometers. Furthermore, increasing the NPs' aspect ratio from 12:1 to 50:1 to produce NPs with a corresponding reduction in the NP bending stiffness of 2 orders of magnitude amplified the cellular response and resulted in a previously unseen degree of cell polarization and alignment. The rapid morphological transformation is reproducible on surfaces that maintain key parameters of the NP geometry and spacing, is influenced by the cell seeding density, and persists for different stem cell lines and primary mesenchymal stem cells. The demonstrated ability to support various morphogenetic trends in stem cells by simply tuning the geometry of the NP substrates provides a stepping-stone for the future design of scaffolds where cellular morphology and alignment are crucial.

Alloys and intermetallic compounds of Au with the 3d transition metals Fe, Co, and Ni are nonequilibrium phases that have many useful potential applications as catalytic, magnetic, optic, and multifunctional magneto-optic materials. However, the atomically ordered Au-M (M = Fe, Co, Ni) intermetallics are particularly elusive from a synthetic standpoint. Here we report the low-temperature solution synthesis of the L12 (Cu3Au-type) intermetallic compounds Au3Fe, Au3Co, and Au3Ni using n-butyllithium as a reducing agent. Reaction pathway studies for the Au3Co system indicate that Au nucleates first, followed by Co incorporation to form the intermetallic. The nonequilibrium intermetallic nanocrystals have been characterized by powder XRD, TEM, EDS, selected area electron diffraction, and nanobeam electron diffraction, which collectively confirm the compositions and superlattice structures.