Photocatalysis in Two-Dimensional Black Phosphorus: The Roles of Many-Body Effects

Two-dimensional (2D) black phosphorus (BP) has drawn tremendous attention in solar-light-driven catalytic processes for its intriguing chemical and physical properties. Benefiting from the highly anisotropic electronic structure induced by its puckered crystal geometry, 2D BP tends to have greater confinement with respect to traditional inorganic nanomaterials, thereby leading to robust many-body effects. Such Coulomb-interaction-mediated effects dominate the electronic and optical properties of 2D BP-based nanosystems, where exotic correlations between photoinduced species give rise to unique photoexcitation processes that are closely associated with the involved photocatalytic behavior. In this Perspective, we highlight the critical role of many-body effects in 2D BP-based photocatalysis and exemplify the relationships between the correlated photoinduced species-dominated photoexcitation processes and photocatalytic behavior involved therein. The relevant challenges and opportunities in pursuing efficient 2D BP-based solar energy utilization are also discussed.