Strategies and Applications for Improving the Stability of Black Phosphorus in Physical Environment

As a new type of 2D material, black phosphorus (BP) has been gradually attracting attentions since it was rediscovered in 2014 because of its many excellent properties, such as strong anisotropic properties, optical-response properties, layer-dependent bandgap, and so on. 2D BP is becoming an excellent candidate in the fields of electronics, optics, and so on. However, the applications of 2D BP are greatly limited and challenged by many adverse factors, such as the low yield, poor stability, and high price of BP nanosheets (NSs). Among them, the poor stability of BP is an important factor, which is an urgent problem to be solved. The main reason for its poor stability is the instability of its environment. The degradation factors of 2D BP are studied, including photoinduced degradation and water-catalyzed degradation. At present, some feasible methods are explored to improve the degradation, which include passivation, surface functionalization, and doping metal or nonmetal ions. This review not only clarifies the structure, properties, degradation mechanism, and methods to improve the BP stability, but also shows more strategic means for the design and application of stable BP-based nanocomposite materials in the fields of electronics, optics, biomedicine, and fire safety.