An insight into terahertz electromagnetic interference shielding of two-dimensional titanium carbide thin film: the key role of functional groups

This work experimentally investigates and compares terahertz electromagnetic shielding of micrometer-thick Ti3C2Tx MXene on polyimide prepared by two methods: etched using LiF/HF or HCl/HF from the MAX phase precursor. The later process shows a larger absorption coefficient as well as higher electrical conductivity. Raman spectroscopy and scanning electron microscopy are employed to probe the Tx termination, as well as, the structure of Ti3C2Tx MXene layer. It is found that the degree of oxygen termination resulting from the type of etchant play a significant role in bridging nearby titanium between the Ti3C2Tx MXene flakes. This is observed to increase the continuity of the Ti3C2Tx MXene surface and substantially enhances terahertz radiation shielding.