Preparation of AntiSalt Spray Conductive Silver-Plated Carbon Fiber via Tannic Acid/Metal Ion Complex Inhibitors for Electromagnetic Interference Shielding

Conductive fillers are critical raw materials for many applications. However, vulnerability to salt spray corrosion remains the biggest problem for silver-plated conductive fillers. Herein, highly conductive silver-plated carbon fiber powders (Ag/pCF) were prepared via catechol/polyamine activation and subsequently formed a tannic acid/metal ion (TA@Me) complex inhibition layer. The electromagnetic interference (EMI) shielding effectiveness of the composite fabricated with original Ag/pCF decreased from 106.4 to 90.4 dB after a 4-cycle salt spray corrosion test, while the composites protected by TA@Me remained unchanged above 110 dB. Further research revealed that TA@Me could effectively block the penetration of Cl-, which is the primary corrosive chemical in a salt fog environment. Considering the high conductivity and the excellent antisalt spray performance, the Ag/pCF protected by the efficient TA@Me inhibition layer via an eco-friendly approach will be a priority alternative for high-performance EMI-shielding applications.