Rational Design of Flexible Two-Dimensional MXenes with Multiple Functionalities

Abstract

In the past decade, two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides (MXenes) have attracted attention and interest from the scientific community due to their superior mechanical strength and flexibility, physical/chemical properties, and multiple exciting functionalities. Among these materials, the ingenious and effective combination of the mechanical and functional properties of MXenes provides a promising opportunity for designing flexible and wearable devices. This review summarizes the recent research progress in the structural stabilities, mechanical strength and deformation mechanism, strain-tunable energy storages, and catalytic and thermoelectric properties along with certain strain modifications and strain-controllable electronic/topological properties of MXenes from a combined theoretical and experimental perspective and illustrates their electronic origins. Taking the design principles as a focus, the theoretical predictions provide guidance, while the experimental work gives a thorough validation, thus setting the foundation for the current scientific achievements, challenges, and prospects in the field of MXenes.

Partial Atomic Tin Nanocomplex Pillared Few-Layered Ti3C2Tx MXenes for Superior Lithium-Ion Storage

“…The final chemical formula of MXenes can be denoted as M n+1 X n T x ; the meaning of each letter is the same as that of MAX phases (M n+1 AX n ), except for T x representing terminated -OH, -F, and -O functional groups at surface [8,9]. Although MXenes show promising application prospect in energy storage [10][11][12], the practical electrochemical performance of MXenes falls short of expectations [13]. This poor result is probably due to the blocking effect of surface anion and excessive accumulation of layers [14][15][16].…”

The Recent Advances in the Mechanical Properties of Self-Standing Two-Dimensional MXene-Based Nanostructures: Deep Insights into the Supercapacitor

“…There are numerous published reviews in the fields of MXenes for energy, catalysis, and environmental remediation [ 12 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. However, the reviews on the mechanical properties of self-standing MXenes are not yet reported [ 24 ]. Many studies have shown that MXenes exhibits excellent mechanical ion adsorption properties, which in turn will set the stage for exploring the possibility of their use in sensors and flexible devices [ 6 , 24 , 25 , 26 ].…”

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

“…Compared to other nanomaterials, MXenes possess the following attractive properties that suitable for cancer therapy. (i) In the presence of functional groups, such as -OH, -O, or -F, MXenes are hydrophilic in nature [9,11], indicating substantial potential for surface modification.…”

“…Because of their unique graphene-like structure, they were named MXenes. In terms of the precursors, more than 90 MAX-phase and non-MAXphase precursors have been reported to fabricate MXenes [9,10]. MAX phase is a family of layered ternary carbides, nitrides, and carbonitrides consisting of "M", "A", and "X" layers.…”