2D layered black arsenic-phosphorus materials: Synthesis, properties, and device applications

Phosphorene, especially black phosphorus (BP), has attracted considerable attention due to the unique characteristics, such as tunable direct bandgap, high carrier mobility, and strong in-plane anisotropy. Recently, a new modification strategy for black phosphorus has been developed by alloying black phosphorus with the congener element arsenic. The elemental composition tuning of black phosphorus with arsenic can not only maintain its special crystal structure and high anisotropy but also modify its electrical and optical properties for the further applications of multifunctional devices. The achieved two-dimensional (2D) black arsenic-phosphorus materials exhibit outstanding optical, electrical, and photoelectric properties, such as very narrow band gap, anisotropic infrared absorption, and bipolar transfer characteristics, presenting great potential in infrared photodetectors and high-performance field effect transistors (FETs). In this review, we introduce the recent progress made in the synthesis and applications of black arsenic-phosphorus, and provide an outlook and perspectives on the current challenges and future opportunities in this field. We hope that this review can bring new insights and inspirations on the further development of 2D black arsenic-phosphorus based materials and devices.