Emerging 2D pnictogens for catalytic applications: status and challenges

The exfoliation of phosphorene from black phosphorus to afford mono-elemental two-dimensional (2D) materials (Xenes) has caused a boom in various fields since 2014. Among the Xenes, an emerging class of material, 2D pnictogens, which includes phosphorene, arsenene, antimonene, and bismuthene, has drawn a great deal of attention in the field of catalysis owing to their high specific surface area, mechanical properties, biocompatibility, and optical and electrical performance. With the development of interdisciplinary research, it has become a new trend of scientific research, especially the application of catalysis in medicine, to break the barriers between disciplines and achieve multidisciplinary joint investigation. Herein, firstly, the structures, general properties, and synthetic methods of 2D pnictogen (group VA) materials are reviewed. Then, we summarize the various state-of-the-art catalytic applications of the 2D pnictogen family, such as photocatalysis, electrocatalysis, and medical catalysis, especially in terms of strategies to improve their catalytic performance, such as doping, functionalization, and heterostructures. We also shed some light on the cross-subject of photocatalytic and electrocatalytic processes for biomedical applications. Finally, we summarize the research progress, outlooks, and challenges for these 2D catalysts in terms of their catalytic performance, characterization, reaction mechanisms, exploration of new systems, and commercial applications. This review aims to highlight the catalytic effects of 2D pnictogen materials in enhancing the performance of reactions.