A review of recent progress in 2D MXenes: Synthesis, properties, and applications

Two-dimensional transition metal carbides/carbonitrides (MXenes) have their unique compositions have helped them obtain properties that are useful in various fields of applications such as batteries, supercapacitors, photo and electrocatalysts, bio-sensors, gas-sensors, water purification, water splitting, lubricants, electronics, elec-tromagnetic interference shielding and so on. This review focuses on the synthesis, properties, and demonstrated wide application prospects in catalytic and energy conversion, mostly in the form of energy storage field ap-plications. MXene composites with optimized reduction time show high catalytic performances and good cycle stability for various model catalytic reactions, providing a new strategy for the study of catalytic composite materials related to the degradation of wastewater. The photocatalytic performance of MXene composites for the degradation of several dyes and volatile organic compounds was also investigated. Then we summarize the primary synthetic methods for each kind of porous MXenes and discuss their applications for pseudo-capacitors, lithium/sodium batteries, lithium-sulfur batteries, sensors, and energy storage applications. We lastly conclude with a brief perspective on future opportunities and challenges of 2D MXenes.