TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The step of heating the copper salt solution and reducing agent solution is performed at 30-45 degrees C or 45-50 degrees C. The addition step is performed in less than 5 minutes, preferably less than 1 minute. Preferred Components: The copper salt is copper halide (including copper chloride (preferred), copper bromide or copper iodide), copper nitrate, copper acetate, copper sulfate, copper formate or copper oxide. The copper nanoparticles have a size of 1-10 (preferably 1-5 or 5-10) nm.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The organic solvent is triglyme. The N,N'-dialkylethylenediamine comprises a 1-4C N,N'-dialkylethylenediamine. The 6-18C alkylamine is a 7-10C alkylamine, preferably n-heptylamine, n-octylamine or n-nonylamine. The reducing agent is sodium borhohydride. In the surfactant system, the N,N'-dialkylethylenediamine and the 6-18C alkylamine are present at a ratio of 1:1 to 2:1. EXAMPLE - Copper(II) chloride dihydrate (0.8 g) was placed into a 250 ml 3 neck round bottom flask, evacuated and back-filled with argon three times, and N,N'-di-tert-butylethylenediamine (4 ml), n-nonylamine (4 ml) and degassed triglyme (45 ml) as the reaction medium were added. The color of the solution turned dark blue and was stirred and heated for 2 hours at 45 degrees C. A second 250 ml 3 neck round bottom flask was charged with dry 2 M sodium borohydride solution (8 ml), and nonylamine (4 ml) and N,N'-di-tert-butylethylenediamine (6 ml) were added. The resulting solution was colorless, and was heated to 45 degrees C and stirred for 1 hour, when heat was applied to this solution, it turned slightly cloudy. While keeping both flasks at 40 degrees C, the copper (II) chloride solution was transferred to the flask containing sodium borohydride for 5 minutes using a cannula. When transfer was complete the reaction looked dark purple. In 10 minutes, the mixture turned cloudy and stayed white for 4 minutes. Subsequently, the reaction kept changing color from white, to yellow-brown and eventually became dark brown over the next 5 minutes. At this point, it was cooled down to -10 degrees C in a dry ice and acetone bath for 10 minutes. The reaction mixture was centrifuged at 1000 rpm for 20 minutes to give a dark brown precipitate and a clear supernatant. The black precipitate was mixed with a solution of degassed hexane (80 ml) and dicyclohexylamine (10 ml), which was then sonicated for 10 minutes. The new mixture was centrifuged at 1000 rpm for 10 minutes to give a black precipitate and clear supernatant. The black precipitate was mixed with a solution of degassed toluene (80 ml) and dicyclohexylamine (10 ml), which was then sonicated and centrifuged at 1000 rpm for 10 minutes to give a black precipitate and a clear supernatant. Degassed deionized water (40 ml), toluene (40 ml) and dicyclohexylamine(5 ml) were added to the black precipitate. The mixture was shaken and sonicated for 10 minutes to mix and disperse everything. The addition of the deionized water caused some gas evolution and bubbling. Then, the mixture was sonicated and centrifuged at 1000 rpm for 20 minutes to give a dark brown organic layer (top layer), a second slightly cloudy aqueous layer (middle layer) and a small amount of a dark brown/copper color precipitate (bottom layer). The organic layer as well as the precipitate were isolated and stored in a glass vial under Argon and kept in a freezer at - 5 degrees C to give copper nanoparticles.