Preparation of graphene-coated Cu particles with oxidation resistance by flash joule heating

Cu particles are limited in their applications due to their susceptibility to oxidation. Here we report a cost-effective method for producing Cu particles with oxidation resistance. By heating the mixture of basic cupric carbonate and glucose powders, Cu particles coated with amorphous carbon were achieved. The amorphous carbon was then converted into graphene through flash joule heating (FJH). The conductivity of the final product was 47.1 S/cm after FJH, which remained as 42.3 S/cm even after in hot air for 30 min, i.e., 89.8% conductivity retention. The product was demonstrated for the application of electromagnetic interference (EMI) shielding with an average EMI shielding effectiveness of 12.3 dB and 11.7 dB before and after oxidizing treatment, respectively.