The carrier dynamics for self-assembled black phosphorus and perovskite nanocrystals enable photocatalytic conversion

Few-layer black phosphorus (BP) becomes an ideal self-assembled material with perovskite nanocrystals (NCs) for photoluminescence (PL) and photocatalysis, due to the feasible control of photogenerated charge carriers. Until now, it is still a challenge to figure out the intrinsic carrier dynamics for multifunctional photodegradation in water. In this work, a series of few-layer BP components were successfully incorporated into CsPbBr₃ NCs to achieve apparent PL quenching and ˙O₂^--dominated photocatalytic degradation of rhodamine B in aqueous solution. The strategy of BP modification can extend photoabsorption ensuring optimized photocatalytic activity by facilitating electron transfer from CsPbBr₃ to BP with strong van der Waals interactions. In particular, CsPbBr₃:5%BP NC eliminates the effect of sub-bandgap luminescence centers, resulting in a low charge transfer resistance, good carrier mobility, and high photocurrent densities under light irradiation.