Multi-reflection-enhanced electromagnetic interference shielding performance of conductive nanocomposite coatings on fabrics.

With the rapid development of electronic communications, coated fabrics with EMI shielding capability have attracted increasing attention due to their broad applications in military, civilian, and commercial fields. The coating structure plays a vital role in EMI shielding performance and the fundamental understanding of how the coating structure affects the EMI shielding performance of the coated fabric is urgently needed. In this work, the coating structure has been systematically modulated to study its effects on the shielding performance of the corresponding coated fabric for the rational design of the high-performance EMI shielding materials. Owing to the multiple reflections of the electromagnetic waves triggered by the graphene oxide (GO)/ polypyrrole (PPy) interfaces, the shielding effectiveness (SE) of the coated fabric reaches 39.1 dB by increasing the amount of interface in the coating. Furthermore, more GO/PPy interfaces in the coating results in stronger EMI shielding enhancement once the conductive network is built. This work provides a guideline for the judicious design of shields to achieve excellent EMI shielding performances and offers opportunities for new-generation portable and wearable EMI shielding products.