Dumbbell-like nanoparticles and a process of forming the same
Dumbbell-shaped or flower-shaped nanoparticles and a process of forming the same, wherein the process comprises forming a mixture of a nanoparticle with a precursor in a first solvent, wherein the nanoparticle comprises a hydrophobic outer coating; heating the mixture; cooling the mixture to room temperature; modifying the hydrophobic outer coating into a hydrophilic outer coating; precipitating a solid product from the mixture, and dispersing the product in a second solvent. The nanoparticles comprise any of a semiconducting, magnetic, and noble metallic material, wherein the nanoparticles comprise a first portion comprising any of PbSe, PbS, CdSe, CdS, ZnS, Au, Ag, Pd, and Pt, and wherein the precursor comprises any of a cationic, neutral or particulate Au, Ag, Pd, Pt, or transition metal (Fe, Co, Ni) precursors of Fe(CO) 5 , Co(CO) 8 , Ni(CO) 4 or their analogues. The first and second solvents comprise any of alkanes, arenes, ethers, nitrites, ketones, and chlorinated hydrocarbons.
1. A process of making multi-functional nanoparticles water-soluble, said process comprising:
mixing nanoparticles of one of a metal sulfide, a metal selenide, and a metal with a noble metal precursor in a first solvent, to form a first mixture of said multi-functional nanoparticles,
wherein each of said multi-functional nanoparticles comprises a single noble metal portion bound to one or more portions of one of said metal sulfide, said metal selenide, and said metal, which differs from said noble metal;
heating said first mixture;
cooling said first mixture to room temperature;
separating said multi-functional nanoparticles from said first mixture,
wherein said multi-functional nanoparticles have a hydrophobic coating;
dispersing said multi-functional nanoparticles with said hydrophobic coating in an organic solvent to form a dispersion;
mixing said dispersion with an aqueous solution of a surfactant to form multi-functional nanoparticles with a hydrophilic coating;
removing said organic solvent from said dispersion;
separating said multi-functional nanoparticles with said hydrophilic coating from said dispersion; and
dispersing said multi-functional nanoparticles with a hydrophilic coating in water.
2. The process of claim 1 , wherein said hydrophobic coating comprises any of hydrocarbons, ethers, and esters.
3. The process of claim 1 , wherein said hydrophilic coating comprises any of —OH, —COOH, —NH2, —CON—, —CN, and ionic groups.
4. The process of claim 1 , wherein a reaction temperature for said process of making multi-function nanoparticles water-soluble is in a range of room temperature to 150° C.
5. A process of making multi-functional nanoparticles water-soluble, said process comprising:
forming multi-function nanoparticles in a mixture containing an organic solvent,
wherein each of said multi-functional nanoparticles comprises a single noble metal portion bound to one or more portions of one of a metal sulfide, a metal selenide, and a metal, which differs from said noble metal, and
wherein said multi-functional nanoparticles have a hydrophobic coating;
dispersing said multi-functional nanoparticles with said hydrophobic coating in an organic solvent to form a dispersion;
mixing said dispersion with an aqueous solution of a surfactant to form multi-functional nanoparticles with a hydrophilic coating;
removing said organic solvent from said dispersion;
separating said multi-functional nanoparticles with said hydrophilic coating from said dispersion; and
dispersing said multi-functional nanoparticles with a hydrophilic coating in water.
6. The process of claim 5 , wherein said hydrophobic coating comprises any of hydrocarbons, ethers, and esters.
7. The process of claim 5 , wherein said hydrophilic coating comprises any of —OH,
—COOH, —NH2, —CON—, —CN, and ionic groups.
8. The process of claim 5 , wherein said hydrophobic coating and said hydrophilic coating, each form a bilayer structure for said multi-functional nanoparticles.