Graphene-Inspired Mono-Elemental 2D Materials: Synthesis, Properties, and Potential Applications of Xenes

Xenes, a class of mono-elemental two-dimensional (2D) materials, have emerged as promising candidate materials for next-generation electronic and energy devices due to their unique structural and electronic properties. This review first systematically categorizes the eighteen experimentally realized Xenes into Group III–VI and other group categories, summarizing their synthesis routes, ranging from top-down exfoliation to bottom-up methods. Based on density functional theory (DFT), this paper focuses on theoretical predictions of stable phases and substrate interactions, which guide experimental preparation. Second, functional applications of Xenes in electronics, optoelectronics, catalysis, energy storage, and biomedicine are also reviewed. The impact of atomic configurations on synthesis difficulty, environmental stability, and scalability across different element groups is also discussed. Finally, emerging strategies such as encapsulation, heterostructure design, and machine learning-guided growth are evaluated to overcome inherent limitations. This paper provides a comprehensive overview of synthesis principles, structure-property relationships, and stabilization strategies, offering insights into future scalable and robust Xene development directions.