Construction of an S-scheme heterojunction with ultra-fast charge transfer at the BP/MOF-808 interface for efficient visible light degradation of metronidazole in the environment

Emerging S-scheme heterojunctions provide catalysts with superior electron transfer pathways and strong redox capacities. Constructing S-scheme heterojunction with two-dimensional nanosemiconductors (with very narrow bandgaps) as interfaces to activate the redox capacity of organic semiconductors (with wide bandgaps) represents a novel method for achieving efficient visible-light photocatalytic degradation of antibiotics. In this study, a BP/MOF-808 S-scheme heterojunction was synthesized through an hydrothermal method. Under visible light excitation (lambda = 460 nm), it was demonstrated that photogenerated electrons are transferred from MOF-808 to BP, thereby retaining strong redox capability within the catalytic system. The 3-BP/MOF-808 (300 mg BP) heterojunction exhibited optimal photocatalytic activity, approximately 27.77 times and 27.34 times higher than those of BP and MOF-808, respectively. The results of this work are expected to guide the design and transformation of S-scheme photocatalysts for efficient environmental degradation of antibiotics.