The introduction of amino termination on Ti3C2 MXene surface for its flexible film with excellent property

The chemical conversion of the surface termination of 2D transition metal carbides/nitrides (MXenes) has opened up a design space that previously had not been extensively explored for this functional material. Herein, via a simple sealed thermal method, the amino terminated groups were successfully introduced on Ti3C2 MXene surface. The substitution reaction of amino group to hydroxyl group was proposed to elucidate this aminated process. As the amination would reduce the carrier density on the surface of MXene, the electrical conductivity of MXene-NH2 film decreased, while it still reached a high conductivity of 2.11 x 10(4) S m(-1). This film also possessed an excellent electromagnetic interference shielding effectiveness of 16160 dB cm(2) g(-1). Importantly, although the introduction of amino termination altered Zeta potential value, Zeta potential sign remained negative and the MXene-NH2 exhibited excellent dispersity in water similar to that of traditional MXenes. Furthermore, the existence of covalent bonds endowed MXene-NH2 polymer composite film with improved mechanical properties. Compared with that of traditional CMC/MXene film, the tensile strength and fracture energy of CMC/MXene-NH2 increased by 65.5% and 132.7%, respectively. These results demonstrated that the introduction of amino terminated group on MXene surface would be an effective strategy to obtain higher performance MXene-based films. (C) 2021 Elsevier Ltd. All rights reserved.