Development of Electromagnetic-Wave-Shielding Polyvinylidene Fluoride–Ti3C2Tx MXene–Carbon Nanotube Composites by Improving Impedance Matching and Conductivity

Abstract

Absorption-dominated electromagnetic interference (EMI) shielding is attained by improving impedance matching and conductivity through structural design. Polyvinylidene fluoride (PVDF)–Ti3C2Tx MXene–single-walled carbon nanotubes (SWCNTs) composites with layered heterogeneous conductive fillers and segregated structures were prepared through electrostatic flocculation and hot pressing of the PVDF composite microsphere-coated MXene and SWCNTs in a layer-by-layer fashion. Results suggest that the heterogeneous fillers improve impedance matching and layered coating, and hot compression allows the MXene and SWCNTs to form a continuous conducting network at the PVDF interface, thereby conferring excellent conductivity to the composite. The PVDF-MXene-SWCNTs composite showed a conductivity of 2.75 S cm−1 at 2.5% MXene and 1% SWCNTs. The EMI shielding efficiency (SE) and contribution from absorption loss to the total EMI SE of PVDF-MXene-SWCNTs were 46.1 dB and 85.7%, respectively. Furthermore, the PVDF-MXene-SWCNTs composite exhibited excellent dielectric losses and impedance matching. Therefore, the layered heteroconductive fillers in a segregated structure optimize impedance matching, provide excellent conductivity, and improve absorption-dominated electromagnetic shielding.

Structural design and preparation of Ti3C2TxMXene/polymer composites for absorption-dominated electromagnetic interference shielding

“…Our previous research 189 confirmed the importance of optimized impedance matching for absorption-dominated efficient EMI shielding of MXene/polymer composites. The above comparisons show that MXene/polymer composites with different Z r values exhibit different EMI SE.…”

Flexible Sandwich-Shaped Cellulose Nanocrystals/Silver Nanowires/MXene Films Exhibit Efficient Electromagnetic-Shielding Interference Performance

“…Sandwiched composite films were prepared by layer-by-layer filtration using MXene as the intermediate layer and mixed solutions of AgNWs and CNC as the upper and lower layers with a symmetric architecture, and the composite films had a diameter of 4 cm. In Figure 2a, the XRD image of MXene shows that the (002) peak of etched Ti 3 C 2 T x MXene is shifted to a lower angle with respect to Ti 3 AlC 2 , which indicates that the Al atomic layer was successfully etched in Ti 3 AlC 2 [51]. The thickness of the monolayer Ti 3 C 2 T x MXene obtained by ultrasonic stripping is about 2 nm, as can be seen from the TEM and AFM of the MXene in Figure 2b,d.…”