The spontaneous assembly of chiral structures from building blocks that lack chirality is fundamentally important for colloidal chemistry and has implications for the formation of advanced optical materials. Here, we find that purified achiral gold tetrahedron-shaped nanoparticles assemble into two-dimensional superlattices that exhibit planar chirality under a balance of repulsive electrostatic and attractive van der Waals and depletion forces. A model accounting for these interactions shows that the growth of planar structures is kinetically preferred over similar three-dimensional products, explaining their selective formation.

Methods for producing multifaceted nanoparticles and uses thereof are disclosed. One method for producing multifaceted nanoparticles can include obtaining a template that includes a substrate and a polymer brush having a plurality of polymers each attached by a first end to the substrate and each having a free opposing second end located opposite the first end; contacting the polymer brush with a solution that includes a nanoparticle precursor material; and forming, from the precursor material and the functional groups located on the second end of the plurality of polymers, multifaceted nanoparticles. The second ends of the polymer chains are functionalized with functional groups that have an affinity for the facets of the multifaceted nanoparticles.

Methods for producing silver nanostructures with improved dimensional control, yield, purity, monodispersity, and scale of synthesis.

The present disclosure relates to a method for manufacturing a metal nanostructure having a chiral structure. The method for manufacturing a metal nanostructure comprises: preparing a first mixture solution by mixing a metal precursor, a surfactant, and a reducing agent; preparing a second mixture solution by adding a peptide to the first mixture solution; and preparing a metal nanostructure having a chiral structure by adding a metal seed particle to the second mixture solution.

Methods for forming samples of noble metal bipyramid nanocrystals having very low size and shape polydispersities from samples of mixed noble metal nanocrystals are provided. The samples include those comprising high purity, substantially monodisperse, plasmonic gold bipyramid nanocrystals. Also provided are methods of growing secondary twinned metal nanocrystals using the noble metal bipyramid nanocrystals as seed particles. Like the seed bipyramid nanocrystals from which they are grown, the secondary nanocrystals are twinned nanocrystals and may also be characterized by very low size and shape polydispersities. Secondary twinned nanocrystals grown by these methods include enlarged metal bipyramid nanocrystals and nanocrystals with anisotropic dumbbell shapes having a variety of tip geometries. Methods for using noble metal bipyramid nanocrystals as plasmonic heaters to heat reaction solutions via plasmonic-photothermal radiation-to-heat conversion are also provided.

Described herein are metallic excavated nanoframes and methods for producing metallic excavated nanoframes. A method may include providing a solution including a plurality of excavated nanoparticles dispersed in a solvent, and exposing the solution to chemical corrosion to convert the plurality of excavated nanoparticles into a plurality of excavated nanoframes.

A method of preparing shape-controlled alloy particles includes dissolving a solvent in a surfactant selected to inhibit particle growth; adding a noble metal precursor and a transition metal precursor to form a mixture; irradiating the mixture with a microwave under reflux for about thirty minutes or less at an irradiation temperature of between 185 C. and 195 C.; cooling the mixture; and drying the mixture at a temperature of between 55 C. and 65 C. to obtain shape-controlled alloy particles having a uniform shape, the shape dependent upon the surfactant used.

A general and well-controlled method for synthesizing intermetallic nanoparticles is provided. The method comprises: preparing noble-metal nanoparticle seeds; dispersing a metal precursor into the noble-metal nanoparticle seeds to form a first solution; adding the first solution into an organic solvent to form a first mixture; sonicating the first mixture at room temperature; subjecting the first mixture to a heat treatment under N.sub.2 atmosphere to render a second solution; cooling the second solution naturally to room temperature; adding ethanol to the second solution to form a third solution; and collecting the intermetallic nanoparticle from the third solution by centrifugation. The as-synthesized hollow orthorhombic Pd.sub.2Sn alloy nanoparticles can accelerate the cleavage of CC bond when compared with commercial Pd/C and display superior catalytic performance towards glycerol oxidation reaction and potential for promising applications.

A variety of nanostructures are provided having a metal nanowire having a plurality of faces extending along a length of the nanowire, and a plurality of semiconductor nanorods forming two or more nanorod arrays, wherein each of the nanorod arrays is attached to a different surface of the nanowire. For example, in some embodiments, the nanostructure is a silver nanowire having a pentagonal cross section and five faces extending along the length of the nanowire, and metal oxide nanorods forming five nanorod arrays extending along each of the five faces of the silver nanowire. The nanostructures can demonstrate high temperature coefficients of resistance, and can be used in a variety of bolometric materials. In some embodiments, bolometric materials are provided including a plurality of the nanostructures deposited onto a surface of a substrate. Methods of making the nanostructures and bolometers are also provided.

In one aspect, compositions comprising copper-silica (CuSiO.sub.2) core-shell nanoparticles are described herein. The core-shell nanoparticles comprise copper (Cu) core components and silica (SiO.sub.2) shell components encapsulating the core components. In some embodiments, the nanoparticle compositions comprise a continuous aqueous phase and a population of copper-silica (CuSiO.sub.2) core-shell nanoparticles dispersed in the aqueous phase.