Construction of liquid metal nanoparticles-decorated on nitrogen-doped Ti3C2Tx MXene with flower-like structure for efficient lithium-ion batteries

Abstract

Two-dimensional (2D) transition metal carbides, nitride compounds, or carbon-nitride compounds (MXenes), has attracted great attention as very popular energy storage materials, since their obvious characteristics compared with other energy storage materials, such as outstanding electrical conductivity, 2D lamellar structure, and abundant surface functional groups. These merits are further boosted by the construction of three-dimensional (3D) structures. Herein, we present a facile strategy of spontaneous converting 2D titanium carbide (Ti3C2Tx) MXene nanoflakes into 3D conductive frameworks of Ti3C2Tx /PANI (TP) composites, which is achieved by conducting oxidation-free polymerization of aniline on the surface of Ti3C2Tx MXene nanosheet, and then introducing liquid metal nanoparticles (LMNPs) with high theoretical capacity into the TP framework to build a 3D hydrangea macrophylla like Ti3C2Tx/PANI/LMNPs (TPL) composite. The TPL composites integrated the unique high-capacity speciality of LMNPs and the conductivity of the MXene framework. Lithium-ion batteries (LIBs) based on TPL electrodes exhibit higher specific capacity of 906.9 mAh g−1 at 0.1 A g−1, capacity retaining ratio of 96.44 % as well as a long cyclic stability (467.0 mAh g−1 after 1500 cycles at 5 A g−1).