Synthesis metal nanoparticle
View Patent ↗A method for providing an anhydrous route for the synthesis of amine capped coinage-metal (copper, silver, and gold) nanoparticles (NPs) using the coinage-metal mesityl (mesityl=C 6 H 2 (CH 3 ) 3 -2,4,6) derivatives. In this method, a solution of (Cu(C 6 H 2 (CH 3 ) 3 ) 5 , (Ag(C 6 H 2 (CH 3 ) 3 ) 4 , or (Au(C 6 H 2 (CH 3 ) 3 ) 5 is dissolved in a coordinating solvent, such as a primary, secondary, or tertiary amine; primary, secondary, or tertiary phosphine, or alkyl thiol, to produce a mesityl precursor solution. This solution is subsequently injected into an organic solvent that is heated to a temperature greater than approximately 100° C. After washing with an organic solvent, such as an alcohol (including methanol, ethanol, propanol, and higher molecular-weight alcohols), oxide free coinage NP are prepared that could be extracted with a solvent, such as an aromatic solvent (including, for example, toluene, benzene, and pyridine) or an alkane (including, for example, pentane, hexane, and heptane). Characterization by UV-Vis spectroscopy and transmission electron microscopy showed that the NPs were approximately 9.2±2.3 nm in size for Cu°, (no surface oxide present), approximately 8.5±1.1 nm Ag° spheres, and approximately 8–80 nm for Au°.
1. A method of making coinage-metal nanoparticles, comprising:
dissolving a solution of a metal mesityl compound, selected from (Cu(C 6 H 2 (CH 3 ) 3 ) 5 , (Ag(C 6 H 2 (CH 3 ) 3 ) 4 , and (Au(C 6 H 2 (CH 3 ) 3 ) 5 , in a coordinating solvent to form a mesityl precursor solution; and mixing said mesityl precursor solution in a second solvent at a temperature greater than approximately 100° C. to form coinage-metal nanoparticles in solution.
2. The method of claim 1 wherein said coordinating solvent is selected from the group consisting of a primary amine, a secondary amine, a tertiary amine, a primary phosphine, a secondary phosphine, a tertiary phosphine, and an alkyl thiol.
3. The method of claim 1 wherein said coordinating solvent is octylamine.
4. The method of claim 1 where said second solvent is selected from the group consisting essentially of a primary amine, a secondary amine, and a tertiary amine.
5. The method of claim 1 further comprising the step of washing the coinage-metal nanoparticles in solution with a first organic solvent to form a precipitate of coinage-metal nanoparticles.
6. The method of claim 5 wherein the first organic solvent is an alcohol.
7. The method of claim 5 further comprising the step of extracting from solution coinage-metal nanoparticles with a solvent selected from an aromatic solvent and an alkane.
8. The method of claim 1 wherein forming coinage-metal nanoparticles in solution was performed under an inert atmosphere.
9. A method of making copper nanoparticles, comprising:
dissolving a solution of (Cu(C 6 H 2 (CH 3 ) 3 ) 5 in an octylamine solvent to form a mesityl precursor solution;
mixing said mesityl precursor solution in a hexadecylamine solvent at a temperature of approximately 300° C. to form coinage-metal nanoparticles in solution;
adding methanol to form a precipitate; and
separating the precipitate to form copper nanoparticles with diameters of approximately 8 nm.
10. A method of making silver nanoparticles, comprising:
dissolving a solution of (Ag(C 6 H 2 (CH 3 ) 3 ) 4 in an octylamine solvent to form a mesityl precursor solution;
mixing said mesityl precursor solution in a hexadecylamine solvent at a temperature of approximately 300° C. to form coinage-metal nanoparticles in solution;
adding methanol to form a precipitate; and
separating the precipitate to form silver nanoparticles with diameters of approximately 9 nm.
11. A method of making gold nanoparticles, comprising:
dissolving a solution of (Au(C 6 H 2 (CH 3 ) 3 ) 5 in an octylamine solvent to form a mesityl precursor solution;
mixing said mesityl precursor solution in a hexadecylamine solvent at a temperature greater than 100° C. to form coinage-metal nanoparticles in solution;
adding methanol to form a precipitate; and
separating the precipitate to form gold nanoparticles.
12. The method of claim 11 wherein said temperature was 300° C. to form gold nanoparticles with diameters of between approximately 10 nm to approximately 80 nm.
13. The method of claim 11 wherein said temperature was 190° C. to form gold nanoparticles with diameters of approximately 12 nm.