Electro magnetic interference shielding characteristic of silver coated copper powder

Abstract

The present investigation deals with the synthesis of silver coated copper powder for potential application as filler material in conductive polymers for electro magnetic interference (EMI) shielding. Copper powders were obtained by the reaction of cuprous oxide and, hydrazine in a mixed solvent (H2O:ethanol) at various reaction conditions. The cuprous oxide powder was produced by the reaction of CuSO4, NaOH and D-glucose. The synthesized copper powder was silver coated by its reaction with (NH4)2SO4, C4H4O6KNa and AgNO3. The prepared powders were characterized by XRD, SEM, TGA and XPS. The coaxial transmission line method was used to measure the EMI shielding effectiveness of the powders. The silver coated copper powders exhibited an improved oxidation resistance and higher EMI shielding effectiveness as compared to the uncoated copper powders.

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Investigation on Stranski–Krastanow (SK) Growth Mode of Ag Coating in Cu/Ag Core-Shell Composites

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