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.

A variety of polyhedral nanocages are provided having a hollow interior, ultrathin walls, and well-defined facets of metal atoms. The nanocages can include a variety of precious metals such as Pt, Au, Ru, Rh, or Ir. The metal atoms can take a face-centered cubic structure with {111} facets on the surface. The walls can be thin, sometimes less than 1 nm in thickness or only a few atomic layers in thickness. The nanocages can provide for efficient uses of valuable precious metals, among other things, in catalysis. For example, catalysts are provided exhibiting high mass activities in oxygen reduction reactions. Methods of making and methods of using the nanocages and catalysts are also provided.

In one aspect, the present disclosure pertains to methods of making various noble metal nanoprisms, e.g., gold nanoprisms. In various aspects, the methods can comprise incubating, under dark conditions, a growth solution comprising: (a) a plurality of gold seed structures; (b) a gold precursor, and (c) a photocatalytic intermediary, such that the during incubating step multiply-twinned gold seed structures in the growth solution are preferentially enlarged. The disclosed methods can comprise separating the multiply-twinned gold seed structures from the growth solution based upon the size of the gold seed structures to produce an enriched growth solution. In some aspects, the methods comprise irradiating the enriched growth solution to produce the gold nanoprisms. In some aspects, the disclosed nanoprisms the nanoprisms do comprise silver.

Self-assembly methods are provided for making hedgehog-shaped microparticles or nanoparticles. The method may comprise combining a metal-containing (e.g., Fe, Au) precursor, a chalcogen-containing precursor (e.g., Se, S), and a self-assembly additive (e.g., dodecanethiol (DT), oleylamine (OLA), hexadecyltrimethylammonium bromide (CTAB)). At least one hedgehog-shaped nanoscale, mesoscale, or microscale particle is formed that defines a core region formed of a first material and a plurality of needles connected to and substantially orthogonal to a surface of the core region. The needles comprise a second material. At least one of the first or the second material comprises iron or gold and optionally selenium or sulfur, for example, iron diselenide (FeSe2). Hedgehog-shaped microparticles or nanoparticles formed from such self-assembly methods are also provided. The semiconductor nature of FeSe2 hedgehog-shaped particles enables their utilization in biomimetic catalysis, drug delivery, optics, and energy storage, by way of non-limiting example.

Nanocages are formed by etching nancubes. The nanocubes are added to an aqueous system having an amphiphilic lipid dissolved in an organic solvent (e.g. a hydrophobic alcohol) to form reverse micelles. As the water evaporates the micelles shrink as etching of the flat surface of the nanocubes occurs. In this fashion hollow nanocages are produced. In one embodiment, the nanocage is covalently attached to a polymer shell (e.g. a dextran shell).

The present invention relates to novel gold nanocrystals and nanocrystal shape distributions that have surfaces that are substantially free from organic impurities or films. Specifically, the surfaces are clean relative to the surfaces of gold nanoparticles made using chemical reduction processes that require organic reductants and/or surfactants to grow gold nanoparticles from gold ions in solution.

The invention includes novel electrochemical manufacturing apparatuses and techniques for making the gold-based nanocrystals. The invention further includes pharmaceutical compositions thereof and the use of the gold nanocrystals or suspensions or colloids thereof for the treatment or prevention of diseases or conditions for which gold therapy is already known and more generally for conditions resulting from pathological cellular activation, such as inflammatory (including chronic inflammatory) conditions, autoimmune conditions, hypersensitivity reactions and/or cancerous diseases or conditions. In one embodiment, the condition is mediated by MIF (macrophage migration inhibiting factor).

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.

The present disclosure relates to a seed-growth based method for the synthesis of metal nanoparticles of controlled shape (cubes, cuboids, octahedrons) and size in an aqueous environment, without the use of shape directing agents. The method involves a first step of preparing a solution comprising water, metal seed growth nanoparticles, a metal salt comprising the same metal as the metal seed growth nanoparticles, and a reducing agent; and a second step of heating the solution to between 9 and 130 C. at a rate of between 1 C./min and 5 C./min and at a pressure of between 1 and 5 atm. The method may also be carried out in a reduced oxygen atmosphere and the concentration of oxygen disclosed in the solution may be less than the concentration of oxygen in an oxygen saturated solution.

First, a liquid mixture is obtained by mixing at least a silver compound, a reductant, and a dispersant (S1). Then, the liquid mixture is heated to cause reaction between the silver compound and the reductant and generate first silver particles each having a sheet-like or plate-like shape and second silver particles each having a spherical shape or a shape closer to a sphere than the first silver particles and a particle diameter smaller than a maximum value of a length of a side of each of the first silver particles (S2).