Two-dimensional black phosphorus: Synthesis, modification, properties, and applications

Black phosphorus (BP) discovered a century ago constitutes a new class of two-dimensional (2D) materials and is intensively studied as a 2D semiconductor. The high carrier mobility and tunable and moderate direct bandgap of BP deliver great promise in electronic and optoelectronic applications and the unique intrinsic anisotropy arising from the puckered structure produces extraordinary electronic, optical, transport, thermal, and mechanical properties that can be exploited in the design of new devices. Furthermore, the biodegradability and biocompatibility of BP bode well for biomedical applications. In this review, we discuss recent advances pertaining to the synthesis, modification, properties, and applications of BP and address some of the challenges and opportunities of BP research.