Enhanced heat conductance and microwave absorption of 2D laminated Ti3C2Tx MXene microflakes via steering surface, defects, and interlayer spacing

In this paper, 2D laminated Ti3C2Tx MXene was successfully synthesized via etching the Al layer on Ti3AlC2 precursors in a one-step hydrothermal reaction. Controlling the etching time (t) handily adjusted the defects, surface groups, interlayer spacing, and surface oxide layer of laminated Ti3C2Tx MXene. With the prolonged etching time, the electrical conductivity and heat conductance changed in an inverted U-type. Moreover, the permittivity and low-frequency attenuation ability of Ti3C2Tx were enhanced, but the impedance matching decreased. The laminated Ti3C2Tx MXene harvest a maximal effective bandwidth of 6.32 GHz (RL ≤ −10 dB, 1.4 mm in thickness) with a maximal absorption of − 33.37 dB at t = 72 h and the optimal heat conductance of 2.746 W/(m·K) at t = 12 h. The outstanding comprehensive properties are owing to the synergistic effects of interface, defect/dipole, orientation, and crossing polarizations, caused by 2D laminated structure with appropriate layer spacing, surface functional groups, and defects. Consequent upon this fact, our strategies offer some significant insights for designing high-performance microwave absorption and heat conductance materials.