Liquid-phase exfoliation of black phosphorus and its applications

Interest in two-dimensional (2D) materials is growing exponentially across various scientific and engineering disciplines owing to their fascinating electrical, optical, chemical, and thermal properties. As one of the newest members in the 2D nanomaterial family, black phosphorus (BP), has recently attracted much attention all over the world and shown great potential in novel nanoelectronics owing to its direct and narrow bandgap. Regarding to the scale production of BP and its related electronic devices, liquid-phase exfoliation reveals superior advances when compared with mechanical exfoliation. Remarkably, liquid-phase exfoliated BP flakes and quantum dots (QDs) exhibit exciting properties in electronic, energy storage, sensors, solar cells, photothermal effect, cancer theranostics and photonic devices. In this article, we discuss the exfoliation of BP in diverse solvents and extend the topic from BP flakes to QDs and summarize the significant advances recently made. We also outline future prospects of solution exfoliated BP nanomaterials, and comment on the challenges that need to be overcome for future applications.