Anomalous Radio Frequency Conductivity and Sheet Resistance of 2D Ti₃C₂T _x MXene

Abstract

In this paper, we demonstrate the anomalous radio frequency (RF) performance of a 2D nanomaterial, Ti 3 C 2 T x MXene, by extracting conductivity and sheet resistance at both direct current (DC) and RF. Two-port microstrip transmission lines with detachable top layers, copper ground layer, and end launch connectors were fabricated. MXene transmission lines were manufactured through the deposition of layers with thicknesses of of 2 µm, 1 µm, and 0.2 µm onto polyethylene terephthalate (PET) substrates.Copper transmission lines were fabricated to serve as a benchmark. Two-port S-parameters were measured using a network analyzer from 0.9 GHz to 1.4 GHz and Telegrapher's equation RLGC parameters (per unit length resistance R, inductance L, conductance G, and capacitance C) were extracted. The RF sheet resistance values of MXene films, as well as copper, were extracted from the R-values. S-parameters were simulated with the extracted RF sheet resistance values and a good match was found with the measured values. S-parameters were also simulated using the 4-point conductivity and thickness of the MXene films. The RF conductivity of the MXene coating was found to be 35,000 S/cm, higher than the DC conductivity of the material (10,000-15,000 S/cm). This work gives a guideline on designing MXene-based communication devices which are different from those fabricated with conventional metals. INDEX TERMSConductive 2D nanomaterial, flexible antenna, MXene, radio frequency sheet resistance, Ti 3 C 2 T x , transmission line