A Comprehensive Review of Mxene-Based Emerging Materials for Energy Storage Applications and Future Perspectives

MXenes is a rapidly emerging class of two-dimensional (2D) materials. It exhibits unique properties that make it suitable for a wide range of applications. This review provides a comprehensive overview of the synthesis and processing techniques for MXenes including both bottom-up and top-down approaches. The synthesis of MXene-based composites is explored in detail focusing on Mxene-carbon composites, Mxene-metal oxides, Mxene-metal sulfides, Mxene-polymer composites and MXene-ceramic composites. Key properties of MXenes are examined including structural, electrical, morphological, optical, mechanical, chemical stability, electrical and thermal properties, conductivity, magnetic properties, dielectric charge and catalytic properties. Characterization techniques used to study these properties is also reviewed. Their 2D structure provides a high surface area and unique interlayer spacing, making MXenes ideal for applications in energy storage devices (like supercapacitors and batteries) where surface area and ion transport are critical for performance. The diverse applications of MXenes are presented emphasizing their use in batteries, catalysis, sensors, environmental remediation and supercapacitors. Special attention is given to the supercapacitor applications of MXenes of their potential in energy storage devices. Due to their high capacitance, fast charge/discharge rates, and excellent stability, MXenes are used in supercapacitors, lithium-ion batteries, and sodium-ion batteries. They can store energy more efficiently than many other materials, making them valuable in the quest for efficient, sustainable energy solutions. The progress in MXene supercapacitor devices is providing insights into the latest advancements and future prospects. MXenes are highlighted as versatile materials with significant potential in various technological fields particularly in energy storage. Future research directions and challenges are also outlined for ongoing and future studies in this dynamic area of materials science.