Dynamical Control over Terahertz Electromagnetic Interference Shielding with 2D Ti₃C₂T_y MXene by Ultrafast Optical Pulses

Abstract

High electrical conductivity and strong absorption of electromagnetic radiation in the terahertz (THz) frequency range by metallic 2D MXene Ti 3 C 2 T y make it a promising material for electromagnetic interference shielding, THz detectors, and transparent conducting electrodes. Here, we demonstrate that ultrafast optical pulses with wavelengths straddling the visible range (400 and 800 nm) induce transient broad-band THz transparency in the MXene that persists for nanoseconds. We demonstrate that optically induced transient THz transparency is independent of temperature from 95 to 290 K. This discovery opens new possibilities for development of switchable electromagnetic interference shielding materials and devices that can be rendered partially transparent on demand for transmitting THz signals, or for designing new THz devices such as sensitive optically gated detectors.

Assembling Nano–Microarchitecture for Electromagnetic Absorbers and Smart Devices

“…Mochalin and Titova et al further demonstrated that 2D MXene Ti 3 C 2 T y holds promising potential for EMI shielding, THz detection, and transparent conducting electrodes. [ 116 ] Under ultrafast optical pulses of wavelengths straddling the visible range, MXene present transient broad‐band THz transparency for nanoseconds, with aspiration for designing new EM devices, such as sensitive optically gated detectors.…”

“…A variety of 3D architectures are emerging and making considerable development in EM functions, such as enhanced response, [ 37,47,77,79,101–107 ] multi‐function integration (hydrophobicity, flexibility, self‐cleaning, heat‐insulating, etc. ), [ 63,82,109,110,115,116 ] and flexible tunability (optical, electrical, and thermal regulation, genes sequencing, etc.). [ 60,96,111–115 ] Especially, some crucial physical models and formulas are proposed, such as EHP model, AICT model, and conductive‐network equation for charge transport, [ 48,49,58 ] equivalent‐circuit model for dipole polarization, [ 83 ] and capacitor‐like structure for interfacial polarization, [ 84 ] as well as competitive synergy of two factors (charge transport and dipole polarization) and four basics (interface scattering, microcurrent, micro‐antenna radiation, and dielectric relaxation) for EM energy conversion, [ 57,120,121 ] with in‐depth insight into function‐structure relationship.…”

“…[ 62 ] Furthermore, EM microsensor, communicator, and detector, etc., supply reserve force for breakthrough in faster response, higher intensity, greater stability, stronger sensitivity, lower noise, and so on, undoubtedly as the future of EM absorbers that inspires increasing attentions all over the world. [ 63,115,116 ]…”

“…At the same time, new technologies, new effects, new mechanisms, new materials, and new structures are bringing limitless vitalities to smart devices, and driving them towards integration, diversification, miniaturization, high performance, precision, and so on. [ 36–121 ] Nowadays, around 3D architectures and their smart devices, a new research hotspot in the interdisciplinary fields of physics, chemistry, materials, electronics, and other technical sciences is formed. Thousands of publications have been reported, with exponential growth.…”

“…[ 110 ] Copyright 2017, Wiley‐VCH), detector (top 2) (Reproduced with permission. [ 116 ] Copyright 2019, ACS), microsensor (top 3) (Reproduced with permission. [ 63 ] Copyright 2020, Wiley‐VCH), communicator (bottom) (Reproduced with permission.…”