To begin, prepare 10 milliliters of one milligram per milliliter graphene oxide, or GO suspension in a glass bottle. Sonicate the go suspension for one hour until the GO is well dispersed in distilled water. Prepare a 20 millimolar cupric chloride solution in a glass vial and sonicate the solution until cupric chloride is well dispersed in distilled water.
Next, add 10 milliliters of the 20 millimolar cupric chloride solution to the GO suspension and sonicate the mixture at 70 degrees Celsius for one hour. Prepare a 20 millimolar sodium borohydride solution in a chemical fume hood immediately before use. Add 20 milliliters of the solution to the GO and cupric chloride mixture while stirring with a magnetic bar at 200 RPM.
Then transfer the mixture to a centrifuge tube and spin it at 23, 000 G for 10 minutes at room temperature. Discard the supernatant after centrifugation. To wash the GO copper nano composite mixture, resuspend it with 10 milliliters of distilled water and sonicate the solution to disperse the precipitate evenly.
Next, centrifuge the solution again at 23, 000 G for 10 minutes at room temperature and remove the supernatant. Then add one milliliter of distilled water to the nano composites and sonicate the mixture to disperse the sediment evenly throughout the liquid phase. After transferring the sonicated mixture to another tube, freeze dry the solution at minus 60 degrees Celsius under a vacuum overnight until the nano composites are completely dry.
Store the nano composite powder at minus 20 degrees Celsius until use. Transmission in scanning electron microscopy images confirmed the growth of heterogeneous copper nanoparticles on the GO sheets and energy dispersive X-ray spectroscopy mapping verified that the particles were copper nanoparticles.
