Carboxylate-Decorated Multiwalled Carbon Nanotube/Aramid\nNanofiber Film for Tunable Electromagnetic Interference Shielding\nPerformance and Rapid Electric Heating Capacity

Abstract

Ultrathin\nand multifunctional films are highly desirable for pivotal\ntechnological demands in current society. However, the nanoscale structural\ndesign and fabrication control of these functional films are still\nunderdeveloped and challenged. Herein, carboxylate-decorated multiwalled\ncarbon nanotube (c-MWCNT)/aramid nanofiber (ANF) films were fabricated\nvia vacuum-assisted filtration, followed by hot-pressing. With a c-MWCNT\ncontent of 50 wt %, the hybrid film exhibited a tensile strength of\n57.13 MPa and an electrical conductivity of 708.9 S·m^–1. The c-MWNCT/ANF film also possessed exceptional electromagnetic\ninterference (EMI) shielding performance, whose EMI shielding effectivness\n(SE) and specific SE (SSE/<i>t</i>) value reached 19.68\ndB and 5624.03 dB·cm²·g^–1 in\nthe X band at a thickness of 37 μm, respectively. In addition,\nthe c-MWNCT/ANF film with 50 wt % c-MWNCT loading demonstrated stable\nelectric heating performance, whose surface temperature was higher\nthan 180 °C at a supplied voltage of 10 V. Moreover, the layered\nstructure of the c-MWNCT/ANF film possessed a low voltage drive of\n2 V and a high heating rate of 3.5 °C·s^–1. The tunable EMI shielding capacity, low voltage drive, and high\nheating rate endowed the c-MWNCT/ANF film with great potential for\nsmart garments, EMI shielding management, and personal thermal management\nsystems.