A review on MXenes: new-generation 2D materials for supercapacitors

MXenes are rapidly emerging two-dimensional (2D) materials in the present era of materials science, and they are finding increasing applications in energy storage fields. They are among the most suitable electrode materials for futuristic energy storage devices. The roles of 2D MXenes and their composite materials are crucial in improving the performance of energy storage devices. They can be used as electrodes, conductive additives, and current collectors in energy storage devices such as supercapacitors. In this review, we present the recent advances of 2D MXenes and their composites in supercapacitor applications and discuss factors influencing their performance in supercapacitors, mechanisms involved in capacity improvement, and synthesis and fabrication methods of electrode materials.