This review discusses the synthesis, properties, and applications of MXenes in sustainable energy management. MXenes are two-dimensional materials derived from MAX phases through selective etching of the A layer using various methods, including acids, alkaline solutions, electrochemical processes, and molten salts. The review covers different synthesis routes, such as HF, LiF, and HCl etching, as well as alkaline, electrochemical, and molten salt methods. It also discusses the structural, optical, electronic, and magnetic properties of MXenes, which contribute to their stability and performance in energy applications. The review highlights the role of MXenes in thermal management, solar water desalination, batteries, and supercapacitors. A techno-economic and life cycle analysis is provided to assess the sustainability and commercial viability of MXenes. The review also addresses the technology readiness level of MXenes and future research directions for their application in energy systems. The synthesis methods are evaluated for scalability, cost-effectiveness, and environmental impact. The review emphasizes the importance of optimizing synthesis conditions to achieve high-quality MXenes with desirable properties for various energy applications. The discussion includes the advantages and disadvantages of different synthesis methods, as well as the potential for scalable and sustainable production of MXenes. The review concludes with a perspective on the future of MXene research and development in energy management.This review discusses the synthesis, properties, and applications of MXenes in sustainable energy management. MXenes are two-dimensional materials derived from MAX phases through selective etching of the A layer using various methods, including acids, alkaline solutions, electrochemical processes, and molten salts. The review covers different synthesis routes, such as HF, LiF, and HCl etching, as well as alkaline, electrochemical, and molten salt methods. It also discusses the structural, optical, electronic, and magnetic properties of MXenes, which contribute to their stability and performance in energy applications. The review highlights the role of MXenes in thermal management, solar water desalination, batteries, and supercapacitors. A techno-economic and life cycle analysis is provided to assess the sustainability and commercial viability of MXenes. The review also addresses the technology readiness level of MXenes and future research directions for their application in energy systems. The synthesis methods are evaluated for scalability, cost-effectiveness, and environmental impact. The review emphasizes the importance of optimizing synthesis conditions to achieve high-quality MXenes with desirable properties for various energy applications. The discussion includes the advantages and disadvantages of different synthesis methods, as well as the potential for scalable and sustainable production of MXenes. The review concludes with a perspective on the future of MXene research and development in energy management.