Recent advances and key challenges of the emerging MBenes from synthesis to applications

Abstract Two‐dimensional (2D) transition metal borides (MBenes) as an analog to 2D transition metal carbides/nitrides (MXenes) have been considered promising platform materials for exploring their physical and chemical properties, due to their tunable composition, excellent stability, and good conductivity. Lots of theoretical studies have predicted possible mechanical, magnetic, and catalytic properties of MBenes, which inspired their research in energy storage and conversion applications. However, a detailed review focusing on the synthesis of high‐quality MBene nanosheets and their energy‐related applications is not available. In this review, MBene with different structures and the latest developments in synthesizing high‐quality MBene nanosheets from top‐down exfoliation and down‐top chemical vapor deposition are first summarized. Then, the basic properties of MBene are investigated, including mechanical properties, metallicity, and magnetism. Next, their key applications such as hydrogen production, ammonia production, and energy storage are elaborately discussed. Finally, the future perspectives and key challenges of MBenes's synthesis and applications are briefly provided.