Review of MXene electrochemical microsupercapacitors

The rapid development of miniaturized and wearable electronics has stimulated growing needs for compatible miniaturized energy storage components. Owing to their unlimited lifetime and high-power density, miniaturized electrochemical capacitors (microsupercapacitors) are considered to be an attractive solution for the development of these microelectronics, but they often depend on the choice of electrode materials and fabrication protocols for scalable production. Recently, a new family of two-dimensional transition metal carbides, carbonitride and nitrides (referred to as MXenes) has shown great promise in advanced microsupercapacitors with high energy and power densities. This was achieved thanks to the high pseudocapacitance, metallic conductivity and ease of solution processing of MXene. In this review, recent progress on MXene synthesis, microstructure design, and fabrication strategies of MXene microsupercapacitors are discussed, and their electrochemical performance is summarized. Further, we briefly discuss the technical challenges and future directions.