Advancements, prospects, and challenges in the synthesis and stability of MXenes for energy applications: a comprehensive review

Abstract

MXenes are two-dimensional (2D) transition metal carbides, carbonitrides, and nitrides, often terminated with functional groups such as oxygen, hydroxyl, or fluorine, which enhance their hydrophilicity. These materials are derived from the selective etching of 'A' element atomic layers from MAX phases in acidic solutions containing aqueous fluoride. The unique chemistry and morphology of MXenes enable their use in a variety of applications, including energy storage, electromagnetic interference shielding, antibacterial activity, water nanofiltration, reinforcement, nuclear waste management, and catalysis. This review provides a comprehensive overview of the synthesis of MXenes, their structure, intercalation, delamination, and properties, offering a thorough understanding of the relationship between their nanostructure and electrochemical performance. This understanding is crucial for advancing the study of 2D MXenes in energy harvesting applications. MXene-based energy devices have garnered significant attention in fields such as medicine and industry. However, there are challenges in developing MXene-based sensors, solar cells, photodetectors, batteries, and supercapacitors with high sensitivity, mechanical stability, and long lifetimes. In this work, we present the methods of MXene preparation, computational analyses, and the resulting morphology and electrical properties. The findings from both computational and experimental approaches influence their applications. Specifically, MXene-based sensors exhibit high sensitivity, solar cells demonstrate high efficiency, and batteries offer long lifetimes and excellent mechanical stability. These exceptional properties make MXenes highly suitable for use in advanced wearable devices.

Graphical abstract