A continuous interfacial bridging approach to fabricate ultrastrong hydroxylated carbon nanotubes intercalated MXene films with superior electromagnetic interference shielding and thermal dissipating properties

The emergence of transition metal carbides and nitrides (MXenes) addresses the rising demand for emerging yet favorable multifunctional materials for their utilization in flexible miniaturized electronics and beyond. However, MXenes pose a significant challenge due to their weak interfacial interactions, which result in inferior mechanical properties and structural integrity in MXene films. The continuous interfacial bridging approach involves incorporating hydrogen, ionic, and covalent bondings, and was developed to fabricate ultrastrong hydroxylated carbon nanotubes (HCNT) intercalated Ti 3 C 2 T x MXene (MX) films (MX@HCNT) with superior mechanical properties, electromagnetic interference (EMI) shielding performance, and thermal conductivity. The MX@HCNT films with hydrogen bonding between MX and HCNT were fabricated by vacuum filtration method and were further crosslinked by a conductive Fe 3+ ion (ionic bonding) and glutaraldehyde (GA, covalent bonding) molecules (MX@HCNT/Fe 3+ /GA). As a result, the continuous interfacial bridging approach facilitates the densification of MX nanosheets in the MX@HCNT/Fe 3+ /GA films. The resultant densified MX@HCNT/Fe 3+ /GA films with 50 wt% of HCNT exhibit significantly improved mechanical strength of 277 MPa, toughness of 5.5 MJ·m −3 , EMI shielding effectiveness (EMI SE) of 71.9 dB, and an ultrahigh in-plane thermal conductivity of 106.8 W·m −1 ·K −1 , making it effectively use in flexible devices.