Transparent and flexible electromagnetic interference shielding film based on Ag nanowires/ionic liquids/thermoplastic polyurethane ternary composites

Flexible and transparent electromagnetic interference (EMI) shielding films are desired in various fields. Herein, we propose a simple but effective approach to fabricate the flexible, transparent, and high EMI shielding films based on Ag nanowires (AgNWs)/ionic liquids (ILs)/thermoplastic polyurethane (TPU) ternary composites. Attributed to the formation of the low-density but highly interconnected AgNW network as well as the synergistic effect of AgNWs and ILs on composite conductivity, the as-prepared AgNWs/ILs/TPU film has a transmittance of 67% and an EMI shielding effectiveness of similar to 26.8 dB at 10 GHz. Because of the low areal density of AgNWs, the absolute shielding effectiveness (SSE/t) of AgNWs/ILs/TPU film even reaches to 1.32 x 10(6) dB cm(2) g(-1) at 10 GHz, which is superior to most reported works. More interestingly, the as-prepared film also exhibits good durability and stability in the EMI shielding properties even after 1000 uninterrupted bending cycles or long-term soaking in acidic or alkali solution. These outstanding performances endow the as-prepared film with great potential in flexible and transparent EMI shielding scenarios.

Automated summary

In this study, a simple yet effective method was proposed to fabricate flexible, transparent, and high electromagnetic interference (EMI) shielding films using Ag nanowires (AgNWs)/ionic liquids (ILs)/thermoplastic polyurethane (TPU) ternary composites. The prepared AgNWs/ILs/TPU film exhibited a transmittance of 67% and an EMI shielding effectiveness of about 26.8 dB at 10 GHz, attributed to the low-density but highly interconnected AgNW network and synergistic effect of AgNWs and ILs on composite conductivity. Additionally, the film showed excellent durability and stability in EMI shielding properties even after 1000 bending cycles or exposure to acidic or alkali solutions. These exceptional performances make the prepared film highly promising for flexible and transparent EMI shielding applications.