Multispectral Electromagnetic Shielding Capabilities of 2D MXenes

The increasing prevalence of advanced electronics, mobilities, telecommunication, and medical devices operating across a wide range of EM waves (from ultralow kHz-level to high THz-scale frequencies) necessitates the development of EMI shielding materials operating in multispectral EM bands. MXenes, a class of two-dimensional materials comprising transition metal carbides, nitrides, and carbonitrides, have emerged as cutting-edge functional EMI shielding materials since their initial report in 2016. This is attributed to their exceptional metallic conductivity, expansive surface area, numerous surface terminations, and excellent solution processability. Here, this presentation aims to demonstrate that MXenes can deliver outstanding multispectral EMI shielding capabilities against radio-frequency (RF) waves, GHz-range microwaves, and THz/infrared (IR)-frequency waves, all achieved with minimal thickness and in various structural forms. Pristine MXene films with nanometer-scale thickness effectively interact with EM waves across the RF, GHz, and THz frequency ranges, while simultaneously demonstrating remarkably low IR emissivity. This low IR emissivity is a critical characteristic for applications such as selective thermal management, IR camouflage, stealth, and anti-counterfeiting measures. Through this exploration, we aim to highlight the versatility and efficacy of MXenes in addressing the evolving demands of EMI shielding across a wide range of electromagnetic frequencies and applications.