Black Phosphorus and Polymeric Carbon Nitride Heterostructure for Photoinduced Molecular Oxygen Activation

Metal-free heterostructure photocatalysts composed of black phosphorus (BP) and polymeric carbon nitride (CN) are successfully synthesized via a one-step liquid exfoliation method assisted by sonication. The combination of BP with CN strengthens the visible-light harvesting ability, facilitates the charge separation in the photocatalytic process, and renders promoted activity of photoinduced molecular oxygen activation, such as superoxide radicals (center dot O-2(-)) evolution and H2O2 production. This work highlights that coupling semiconductors with well-matched band levels provide a flexible route to enhance the performance of photocatalysts for producing reactive oxygen species, and gives ideas for the design of highly active and metal-free materials toward sustainable solar-to-chemical energy conversion and environmental remediation.