Interfacial covalent bonding of Ni doped MoS2/TiO2/Ti3C2Tx composites for electromagnetic wave absorption performance

Two-dimensional MXene and its composites are among the most attractive electromagnetic wave absorption (EMA) materials due to their unique structure. While previous studies have investigated 2D/2D MoS 2 /Ti 3 C 2 T x heterojunctions for EMA, there is still a need for further adjustments to interface structure to enhance polarized electron density and electron transfer capacity. In this study, Cl-Ti 3 C 2 T x was prepared by Lewis acid molten salt etching of Ti 3 AlC 2 , and S-Ti 3 C 2 T x was prepared by replacing Cl with S. MoS 2 nanosheets were grown on the surface of S-Ti 3 C 2 T x by a simple hydrothermal method, forming a Ti-S-Mo covalent interface. The EMA properties of the composites were further optimized by adjusting the interface oriented polarization and electronic structure through Ni doping. Compared to MoS 2 /TiO 2 /Ti 3 C 2 T x , the electromagnetic wave absorption performance of Ni-MoS 2 /TiO 2 /Ti 3 C 2 T x had been significantly improved. When the Ni doping amount was 0.086 mmol, the minimum reflection loss of Ni-MoS 2 /TiO 2 /Ti 3 C 2 T x could reach −48.04 dB at 8.64 GHz, with an effective absorption bandwidth of 3.28 GHz. This study provides theoretical basis and experimental evidence for the follow-up research of MXene-based composite EMA materials.